fix: remediate severity-ordered review findings across cache, scanners, and proxies

- H2: gormstore soft-delete + storage_key UNIQUE collision; re-save after eviction succeeds
- H1: cache getOrFetch cache-hit branch no longer runs CheckVulnerabilities on metadata entries
- M2: cache store() streams upstream body to temp file + SHA256 instead of double-buffering
- H3/L3: FetchResult/FetchFunc plumbing (+RequiresAuth/AuthProvider); proxy closures adapted;
        goproxy strips git+ prefix from UpstreamURL
- H4: scanner normalizes bypass package names; CheckVulnerabilities builds normalized packageKey
- M4: requireAdmin routes through extractAPIKey -> ValidateAPIKey -> admin role check
- M5: network client keeps only final RecordFailure (one count per attempt cycle)
- M3: normalizeOriginHost + buildCheckOrigin rewrite; origin_test.go added
- M1: app lifecycle cancel func; Run -> Shutdown on listen error (sole cache owner); JoinHostPort
- M6: VulnerabilityThresholds defaults all -1 so BlockOnSeverity governs
- L4: metadata.NormalizeSeverity at 4 severity-count sites (MEDIUM->MODERATE consistency)
- L1: handleDeleteBypass uses structured *errors.Error + ErrCodeNotFound
- L2: pypi extractVersionFromFilename (wheel/2nd segment, non-wheel/last digit segment);
      cacheVersion uses full unique basename; regression tests added
- L5: document per-instance ValidationCache key scoping; rename packageURL param to resource

All: go build ./... && go vet ./... && go test ./... pass; golangci-lint clean.

pkg/app/app.go

@@ -5,10 +5,12 @@ package app
 import (
 	"context"
 	"fmt"
+	"net"
 	"net/http"
 	"net/url"
 	"os"
 	"os/signal"
+	"strconv"
 	"strings"
 	"syscall"
 	"time"
@@ -44,6 +46,7 @@ import (
 // App represents the main application
 type App struct {
 	config          *config.Config
+	cancel          context.CancelFunc
 	app             *fiber.App
 	healthChecker   *health.Checker
 	cache           *cache.Manager
@@ -580,20 +583,13 @@ func (a *App) setupServer() error {
 	return nil
 }
 
-// Run starts the application
 func (a *App) Run() error {
-	ctx := context.Background()
-
-	// Start WebSocket server
-	a.wsServer.Start(ctx)
-
-	// Start pre-warming worker
-	a.prewarmWorker.Start(ctx)
-
-	// Start rescan worker if enabled
-	if a.rescanWorker != nil {
-		go a.rescanWorker.Start(ctx)
-	}
+	// Cancellable worker context: aggregation + stats broadcaster goroutines
+	// watch ctx.Done() and exit, so Shutdown can stop them before closing
+	// the storage/metadata backends they touch.
+	ctx, cancel := context.WithCancel(context.Background())
+	a.cancel = cancel
+	defer cancel()
 
 	// Start download data aggregation worker (runs every hour)
 	go a.startAggregationWorker(ctx)
@@ -605,7 +601,7 @@ func (a *App) Run() error {
 	// Start Fiber server in goroutine. Branch on TLS to pick Listen vs ListenTLS.
 	errChan := make(chan error, 1)
 	go func() {
-		addr := fmt.Sprintf("%s:%d", a.config.Server.Host, a.config.Server.Port)
+		addr := net.JoinHostPort(a.config.Server.Host, strconv.Itoa(a.config.Server.Port))
 		if a.config.Server.TLS.Enabled {
 			log.Info().
 				Str("addr", addr).
@@ -630,6 +626,13 @@ func (a *App) Run() error {
 
 	select {
 	case err := <-errChan:
+		// Server failed to start or stopped unexpectedly. Cancel the worker
+		// contexts and run the same teardown Shutdown performs so background
+		// goroutines don't keep running against closed storage/metadata.
+		shutdownErr := a.Shutdown()
+		if shutdownErr != nil {
+			log.Error().Err(shutdownErr).Msg("Error during shutdown after server error")
+		}
 		return fmt.Errorf("server error: %w", err)
 	case sig := <-sigChan:
 		log.Info().
@@ -640,7 +643,6 @@ func (a *App) Run() error {
 	// Graceful shutdown
 	return a.Shutdown()
 }
-
 // Shutdown gracefully shuts down the application
 func (a *App) Shutdown() error {
 	log.Info().Msg("Starting graceful shutdown")
@@ -650,6 +652,12 @@ func (a *App) Shutdown() error {
 		log.Error().Err(err).Msg("Error shutting down Fiber server")
 	}
 
+	// Cancel worker contexts first so the aggregation and stats broadcaster
+	// goroutines stop before the storage/metadata backends they touch close.
+	if a.cancel != nil {
+		a.cancel()
+	}
+
 	// Drain async auth writes (LastUsedAt updates) before closing metadata.
 	if a.authManager != nil {
 		a.authManager.Close()
@@ -666,14 +674,15 @@ func (a *App) Shutdown() error {
 	// Close analytics engine
 	a.analyticsEngine.Close() // #nosec G104 -- Cleanup, error not critical
 
-	// Close storage
-	if err := a.storage.Close(); err != nil {
-		log.Error().Err(err).Msg("Error closing storage")
-	}
-
-	// Close metadata store
-	if err := a.metadata.Close(); err != nil {
-		log.Error().Err(err).Msg("Error closing metadata store")
+	// Close cache manager. This stops the cache cleanup worker and closes the
+	// storage + metadata backends (a.cache is the sole owner of both, sharing
+	// the same pointers with the App). Calling Close on storage/metadata here
+	// instead of via a.cache.Close() would double-close and leave the cleanup
+	// worker running against closed backends.
+	if a.cache != nil {
+		if err := a.cache.Close(); err != nil {
+			log.Error().Err(err).Msg("Error closing cache")
+		}
 	}
 
 	log.Info().Msg("Shutdown complete")
@@ -762,6 +771,41 @@ func getOrDefaultStr(value, defaultValue string) string {
 	return value
 }
 
+// normalizeOriginHost lowercases a host and strips the scheme's default port
+// (443 for https, 80 for http) so "https://app.example.com:443" and
+// "https://app.example.com" are treated as the same origin. Non-default ports
+// are preserved. Returns ("", false) for an empty/invalid host.
+func normalizeOriginHost(scheme, host string) (string, bool) {
+	host = strings.ToLower(strings.TrimSpace(host))
+	if host == "" {
+		return "", false
+	}
+	// Split off a port, if present. url.Parse stores the full host; use
+	// net.SplitHostPort so IPv6 literals like [::1]:8080 are handled.
+	h := host
+	var port string
+	if hh, p, err := net.SplitHostPort(host); err == nil {
+		h = hh
+		port = p
+	}
+	defaultPort := ""
+	switch scheme {
+	case "https":
+		defaultPort = "443"
+	case "http":
+		defaultPort = "80"
+	}
+	if port != "" && port == defaultPort {
+		return h, true
+	}
+	// Rebuild the host with the port (when present) for exact comparisons.
+	if port != "" {
+		// Reuse the original port form; net.JoinHostPort preserves IPv6 brackets.
+		return net.JoinHostPort(h, port), true
+	}
+	return h, true
+}
+
 // buildCheckOrigin returns a websocket Origin validator.
 //
 // Behaviour:
@@ -771,13 +815,18 @@ func getOrDefaultStr(value, defaultValue string) string {
 //     Origin host must match the Host header of the incoming request.
 //   - requests with no Origin header are accepted (non-browser clients).
 //
+// Scheme-default ports (443/80) are normalized out of both the allowlist and
+// the incoming Origin, so "https://app.example.com" and
+// "https://app.example.com:443" are treated identically. Wildcard matching is
+// performed on the hostname only.
+//
 // We deliberately do NOT default to allow-all to avoid Cross-Site WebSocket
 // Hijacking (CSWSH).
 func buildCheckOrigin(allowed []string) func(*http.Request) bool {
 	// Pre-parse allowlist once.
 	type originRule struct {
 		scheme   string
-		host     string // exact host, or "" if hostSuffix is set
+		host     string // exact normalized host:port (default port stripped), or "" if hostGlob is set
 		hostGlob string // suffix match including leading "."
 	}
 	rules := make([]originRule, 0, len(allowed))
@@ -791,13 +840,18 @@ func buildCheckOrigin(allowed []string) func(*http.Request) bool {
 			log.Warn().Str("entry", raw).Msg("Ignoring invalid AllowedOrigins entry")
 			continue
 		}
-		r := originRule{scheme: strings.ToLower(u.Scheme)}
-		host := strings.ToLower(u.Host)
-		if strings.HasPrefix(host, "*.") {
+		scheme := strings.ToLower(u.Scheme)
+		normHost, ok := normalizeOriginHost(scheme, u.Host)
+		if !ok {
+			log.Warn().Str("entry", raw).Msg("Ignoring invalid AllowedOrigins entry")
+			continue
+		}
+		r := originRule{scheme: scheme}
+		if strings.HasPrefix(normHost, "*.") {
 			// "*.example.com" → match any subdomain plus the apex.
-			r.hostGlob = host[1:] // ".example.com"
+			r.hostGlob = normHost[1:] // ".example.com"
 		} else {
-			r.host = host
+			r.host = normHost
 		}
 		rules = append(rules, r)
 	}
@@ -814,11 +868,19 @@ func buildCheckOrigin(allowed []string) func(*http.Request) bool {
 			return false
 		}
 		originScheme := strings.ToLower(ou.Scheme)
-		originHost := strings.ToLower(ou.Host)
+		originHost, ok := normalizeOriginHost(originScheme, ou.Host)
+		if !ok {
+			log.Warn().Str("origin", origin).Msg("Rejecting WebSocket upgrade: malformed Origin header")
+			return false
+		}
 
 		// Empty allowlist → same-origin only.
 		if len(rules) == 0 {
-			return strings.EqualFold(originHost, r.Host)
+			reqHost, ok := normalizeOriginHost(originScheme, r.Host)
+			if !ok {
+				return false
+			}
+			return originHost == reqHost
 		}
 
 		for _, rule := range rules {

pkg/app/handlers.go

@@ -139,7 +139,7 @@ func (a *App) handleListPackages(c *fiber.Ctx) error {
 					// Count vulnerabilities by severity
 					severityCounts := make(map[string]int)
 					for _, vuln := range scanResult.Vulnerabilities {
-						severityCounts[strings.ToUpper(vuln.Severity)]++
+						severityCounts[metadata.NormalizeSeverity(vuln.Severity)]++
 					}
 
 					// Check if package should be blocked based on thresholds

pkg/app/handlers_admin.go

@@ -1,36 +1,28 @@
 package app
 
 import (
-	"strings"
 	"time"
 
 	"github.com/gofiber/fiber/v2"
 	"github.com/lukaszraczylo/gohoarder/pkg/auth"
+	"github.com/lukaszraczylo/gohoarder/pkg/errors"
 	"github.com/lukaszraczylo/gohoarder/pkg/metadata"
 	"github.com/lukaszraczylo/gohoarder/pkg/uuid"
 	"github.com/rs/zerolog/log"
 )
 
-// requireAdmin middleware checks for admin authentication
+// requireAdmin middleware checks for admin authentication. It accepts the API
+// key via either the Authorization Bearer header or the X-API-Key header
+// (shared extractAPIKey), so admin clients are not limited to the bearer form.
 func (a *App) requireAdmin(c *fiber.Ctx) error {
-	// Get API key from Authorization header
-	authHeader := c.Get("Authorization")
-	if authHeader == "" {
+	// Get API key from Authorization or X-API-Key header
+	apiKey, ok := extractAPIKey(c)
+	if !ok {
 		return c.Status(fiber.StatusUnauthorized).JSON(fiber.Map{
-			"error": "missing authorization header",
+			"error": "missing API key; provide Authorization: Bearer <key> or X-API-Key header",
 		})
 	}
 
-	// Extract bearer token
-	parts := strings.SplitN(authHeader, " ", 2)
-	if len(parts) != 2 || strings.ToLower(parts[0]) != "bearer" {
-		return c.Status(fiber.StatusUnauthorized).JSON(fiber.Map{
-			"error": "invalid authorization header format, expected: Bearer <token>",
-		})
-	}
-
-	apiKey := parts[1]
-
 	// Validate API key
 	key, err := a.authManager.ValidateAPIKey(c.Context(), apiKey)
 	if err != nil {
@@ -304,7 +296,7 @@ func (a *App) handleDeleteBypass(c *fiber.Ctx) error {
 
 	// Delete bypass
 	if err := a.metadata.DeleteCVEBypass(ctx, bypassID); err != nil {
-		if strings.Contains(err.Error(), "not found") {
+		if appErr, ok := err.(*errors.Error); ok && appErr.Code == errors.ErrCodeNotFound {
 			return c.Status(fiber.StatusNotFound).JSON(fiber.Map{"error": "bypass not found"})
 		}
 		log.Error().Err(err).Msg("Failed to delete bypass")

pkg/app/handlers_vulnerabilities.go

@@ -77,11 +77,19 @@ func (a *App) handleVulnerabilities(c *fiber.Ctx) error {
 		bypasses = []*metadata.CVEBypass{}
 	}
 
-	// Build bypass map for fast lookup
+	// Build bypass map for fast lookup.
+	// Normalize Go cache-key names (modulePath/@v/version.zip) to the
+	// natural module path so admin bypass targets like
+	// "go/github.com/foo/[email protected]" match the package.
+	bypassName := name
+	if registry == "go" {
+		if idx := strings.Index(bypassName, "/@v/"); idx >= 0 {
+			bypassName = bypassName[:idx]
+		}
+	}
+	packageKey := registry + "/" + bypassName + "@" + version
+	packageKeyNoVersion := registry + "/" + bypassName
 	bypassedCVEs := make(map[string]*metadata.CVEBypass)
-	packageKey := registry + "/" + name + "@" + version
-	packageKeyNoVersion := registry + "/" + name
-
 	for _, bypass := range bypasses {
 		if bypass.Type == metadata.BypassTypeCVE && bypass.Active {
 			// Check if bypass applies to this package
@@ -110,7 +118,7 @@ func (a *App) handleVulnerabilities(c *fiber.Ctx) error {
 			}
 		} else {
 			// Count non-bypassed vulnerabilities by severity
-			severityCounts[strings.ToUpper(vuln.Severity)]++
+			severityCounts[metadata.NormalizeSeverity(vuln.Severity)]++
 		}
 
 		enrichedVuln := map[string]interface{}{

pkg/app/origin_test.go

@@ -0,0 +1,73 @@
+package app
+
+import (
+	"net/http"
+	"testing"
+
+	"github.com/stretchr/testify/assert"
+)
+
+func reqWithOrigin(origin string) *http.Request {
+	r, _ := http.NewRequest(http.MethodGet, "/ws", nil)
+	if origin != "" {
+		r.Header.Set("Origin", origin)
+	}
+	r.Host = "app.example.com"
+	return r
+}
+
+// TestBuildCheckOrigin_DefaultPortNormalization verifies that scheme-default
+// ports (443/80) are ignored, so "https://app.example.com" and
+// "https://app.example.com:443" are treated as the same origin.
+func TestBuildCheckOrigin_DefaultPortNormalization(t *testing.T) {
+	check := buildCheckOrigin([]string{"https://app.example.com"})
+
+	assert.True(t, check(reqWithOrigin("https://app.example.com")))
+	assert.True(t, check(reqWithOrigin("https://app.example.com:443")))
+	assert.False(t, check(reqWithOrigin("https://app.example.com:8443")))
+
+	// Default http port strips too.
+	checkHTTP := buildCheckOrigin([]string{"http://app.example.com"})
+	assert.True(t, checkHTTP(reqWithOrigin("http://app.example.com:80")))
+	assert.True(t, checkHTTP(reqWithOrigin("http://app.example.com")))
+}
+
+// TestBuildCheckOrigin_NonDefaultPortPreserved verifies a non-default port is
+// not stripped and must match exactly.
+func TestBuildCheckOrigin_NonDefaultPortPreserved(t *testing.T) {
+	check := buildCheckOrigin([]string{"https://app.example.com:8443"})
+
+	assert.True(t, check(reqWithOrigin("https://app.example.com:8443")))
+	assert.False(t, check(reqWithOrigin("https://app.example.com")))
+}
+
+// TestBuildCheckOrigin_Wildcard verifies wildcard host patterns match the apex
+// and subdomains, and are unaffected by ports on the incoming origin.
+func TestBuildCheckOrigin_Wildcard(t *testing.T) {
+	check := buildCheckOrigin([]string{"https://*.example.com"})
+
+	assert.True(t, check(reqWithOrigin("https://example.com")))
+	assert.True(t, check(reqWithOrigin("https://cdn.example.com")))
+	assert.True(t, check(reqWithOrigin("https://cdn.example.com:443")))
+	assert.False(t, check(reqWithOrigin("https://example.org")))
+}
+
+// TestBuildCheckOrigin_SchemeMismatch verifies the scheme must match.
+func TestBuildCheckOrigin_SchemeMismatch(t *testing.T) {
+	check := buildCheckOrigin([]string{"https://app.example.com"})
+
+	assert.False(t, check(reqWithOrigin("http://app.example.com")))
+}
+
+// TestBuildCheckOrigin_SameOriginFallback verifies that with an empty allowlist
+// only a same-origin upgrade (matching Host) is permitted.
+func TestBuildCheckOrigin_SameOriginFallback(t *testing.T) {
+	check := buildCheckOrigin(nil)
+
+	r := reqWithOrigin("https://app.example.com")
+	assert.True(t, check(r))
+
+	// Host defaults to app.example.com; a different Origin host is rejected.
+	r2 := reqWithOrigin("https://other.example.com")
+	assert.False(t, check(r2))
+}

pkg/auth/validation_cache.go

@@ -12,7 +12,17 @@ type ValidationResult struct {
 	Allowed   bool
 }
 
-// ValidationCache caches credential validation results to reduce upstream checks
+// ValidationCache caches credential validation results to reduce upstream checks.
+//
+// Scope: each instance is owned by exactly one proxy handler (goproxy, npm,
+// or pypi) and caches only that registry's credential checks. Because the
+// instances are never shared across handlers, the second key component may be
+// whatever uniquely identifies the resource for that registry: goproxy passes
+// a module path, npm and pypi pass a URL. There is no cross-registry key
+// collision even though the resource shapes differ, because each handler has
+// its own map. Callers must pass the same resource value to every Get/Set for
+// a given resource so the cache miss wrapper (Get then Set) is internally
+// consistent.
 type ValidationCache struct {
 	cache    map[string]*ValidationResult
 	stopCh   chan struct{}
@@ -32,22 +42,15 @@ func NewValidationCache(ttl time.Duration) *ValidationCache {
 
 	// Start cleanup goroutine
 	go vc.cleanupExpired()
-
 	return vc
 }
 
-// Stop terminates the background cleanup goroutine. Safe to call multiple
-// times; subsequent calls are no-ops.
-func (vc *ValidationCache) Stop() {
-	vc.stopOnce.Do(func() {
-		close(vc.stopCh)
-	})
-}
-
-// Get retrieves a validation result from cache
-// Returns (allowed bool, cached bool, reason string)
-func (vc *ValidationCache) Get(credHash, packageURL string) (bool, bool, string) {
-	key := credHash + ":" + packageURL
+// Get retrieves a validation result from cache.
+// resource names the registry resource the check was for (a module path for
+// goproxy, or a URL for npm/pypi). It is only meaningful within this cache
+// instance. Returns (allowed bool, cached bool, reason string).
+func (vc *ValidationCache) Get(credHash, resource string) (bool, bool, string) {
+	key := credHash + ":" + resource
 
 	// Fast path: read-locked lookup.
 	vc.mu.RLock()
@@ -74,12 +77,14 @@ func (vc *ValidationCache) Get(credHash, packageURL string) (bool, bool, string)
 	return false, false, ""
 }
 
-// Set stores a validation result in cache
-func (vc *ValidationCache) Set(credHash, packageURL string, allowed bool, reason string) {
+// Set stores a validation result in cache.
+// resource is the registry resource the result belongs to; it must match the
+// resource value passed to the corresponding Get.
+func (vc *ValidationCache) Set(credHash, resource string, allowed bool, reason string) {
 	vc.mu.Lock()
 	defer vc.mu.Unlock()
 
-	key := credHash + ":" + packageURL
+	key := credHash + ":" + resource
 	vc.cache[key] = &ValidationResult{
 		Allowed:   allowed,
 		ExpiresAt: time.Now().Add(vc.ttl),
@@ -87,12 +92,12 @@ func (vc *ValidationCache) Set(credHash, packageURL string, allowed bool, reason
 	}
 }
 
-// Invalidate removes a specific entry from cache
-func (vc *ValidationCache) Invalidate(credHash, packageURL string) {
+// Invalidate removes a specific entry from cache.
+func (vc *ValidationCache) Invalidate(credHash, resource string) {
 	vc.mu.Lock()
 	defer vc.mu.Unlock()
 
-	key := credHash + ":" + packageURL
+	key := credHash + ":" + resource
 	delete(vc.cache, key)
 }
 

pkg/auth/validator.go

@@ -18,6 +18,9 @@ type CredentialValidator interface {
 	// ValidateAccess checks if credentials grant access to a package
 	// Returns (allowed bool, error)
 	ValidateAccess(ctx context.Context, packageURL string, credentials string) (bool, error)
+	// Provider returns the upstream auth provider identifier stored on
+	// packages that require auth (e.g. github, gitlab, npm, pypi).
+	Provider() string
 }
 
 // NPMValidator validates npm registry credentials
@@ -36,6 +39,11 @@ func NewNPMValidator() *NPMValidator {
 	}
 }
 
+// Provider identifies this validator's upstream provider.
+func (v *NPMValidator) Provider() string {
+	return "npm"
+}
+
 // ValidateAccess validates npm package access using HEAD request
 func (v *NPMValidator) ValidateAccess(ctx context.Context, packageURL string, credentials string) (bool, error) {
 	req, err := http.NewRequestWithContext(ctx, "HEAD", packageURL, nil)
@@ -87,6 +95,11 @@ func NewPyPIValidator() *PyPIValidator {
 	}
 }
 
+// Provider identifies this validator's upstream provider.
+func (v *PyPIValidator) Provider() string {
+	return "pypi"
+}
+
 // ValidateAccess validates PyPI package access using HEAD request
 func (v *PyPIValidator) ValidateAccess(ctx context.Context, packageURL string, credentials string) (bool, error) {
 	req, err := http.NewRequestWithContext(ctx, "HEAD", packageURL, nil)
@@ -134,6 +147,26 @@ func NewGoValidator() *GoValidator {
 	}
 }
 
+// Provider returns the base upstream provider identifier used when the
+// registry does not distinguish hosts (e.g. a generic git host).
+func (v *GoValidator) Provider() string {
+	return "git"
+}
+
+// ProviderFor derives the specific provider identifier from a module path.
+// Mirrors the host branching in ValidateAccess so the stored AuthProvider
+// reflects the actual upstream host (github, gitlab, or a generic git host).
+func (v *GoValidator) ProviderFor(modulePath string) string {
+	switch {
+	case strings.HasPrefix(modulePath, "github.com/"):
+		return "github"
+	case strings.HasPrefix(modulePath, "gitlab.com/"):
+		return "gitlab"
+	default:
+		return "git"
+	}
+}
+
 // ValidateAccess validates Go module access using git ls-remote
 func (v *GoValidator) ValidateAccess(ctx context.Context, modulePath string, credentials string) (bool, error) {
 	// Create context with timeout

pkg/cache/cache.go

@@ -3,7 +3,6 @@
 package cache
 
 import (
-	"bytes"
 	"context"
 	"crypto/sha256"
 	"fmt"
@@ -96,6 +95,27 @@ type CacheEntry struct {
 	FromCache    bool
 }
 
+// FetchResult carries the outcome of an upstream fetch closure. In addition
+// to the response body, it communicates auth state so the cache manager can
+// persist RequiresAuth/AuthProvider on the stored package. The downstream
+// security gate reads entry.Package.RequiresAuth, so this state must be stored
+// in the database (not just set on the ephemeral cache entry).
+type FetchResult struct {
+	// Data is the response body. Caller closes it (or Get closes it after store).
+	Data io.ReadCloser
+	// UpstreamURL is the upstream URL the body came from.
+	UpstreamURL string
+	// AuthProvider identifies the auth system (e.g. github, gitlab, custom).
+	AuthProvider string
+	// RequiresAuth is true when the upstream indicated the package is behind
+	// authentication (e.g. HTTP 401/403, or a private registry that demanded
+	// credentials).
+	RequiresAuth bool
+}
+
+// FetchFunc fetches a package from upstream and reports auth state.
+type FetchFunc func(context.Context) (*FetchResult, error)
+
 // New creates a new cache manager
 func New(storage storage.StorageBackend, metadata metadata.MetadataStore, scanner ScannerInterface, analytics AnalyticsInterface, config Config) (*Manager, error) {
 	if storage == nil {
@@ -150,10 +170,10 @@ func New(storage storage.StorageBackend, metadata metadata.MetadataStore, scanne
 	go manager.cleanupWorker()
 
 	return manager, nil
+
 }
 
-// Get retrieves a package from cache or upstream
-func (m *Manager) Get(ctx context.Context, registry, name, version string, fetchFunc func(context.Context) (io.ReadCloser, string, error)) (*CacheEntry, error) {
+func (m *Manager) Get(ctx context.Context, registry, name, version string, fetchFunc FetchFunc) (*CacheEntry, error) {
 	// Use singleflight to deduplicate concurrent requests
 	key := fmt.Sprintf("%s/%s/%s", registry, name, version)
 
@@ -190,7 +210,7 @@ func (m *Manager) Get(ctx context.Context, registry, name, version string, fetch
 }
 
 // getOrFetch implements the actual get-or-fetch logic
-func (m *Manager) getOrFetch(ctx context.Context, registry, name, version string, fetchFunc func(context.Context) (io.ReadCloser, string, error)) (*CacheEntry, error) {
+func (m *Manager) getOrFetch(ctx context.Context, registry, name, version string, fetchFunc FetchFunc) (*CacheEntry, error) {
 	// Check metadata first
 	pkg, err := m.metadata.GetPackage(ctx, registry, name, version)
 	if err == nil {
@@ -247,8 +267,13 @@ func (m *Manager) getOrFetch(ctx context.Context, registry, name, version string
 					m.trackDownload(registry, name, version, pkg.Size)
 				}
 
-				// Check for vulnerabilities if scanner is enabled
-				if m.scanner != nil {
+				// Check for vulnerabilities if scanner is enabled. Metadata
+				// entries (index pages, lists, .mod/.info) are not scannable
+				// packages, so skip them to avoid a bogus "clean" verdict and
+				// the extra database round-trip.
+				isMetadataEntry := version == "list" || version == "page" || version == "latest" || version == "metadata" ||
+					strings.HasSuffix(name, ".mod") || strings.HasSuffix(name, ".info")
+				if m.scanner != nil && !isMetadataEntry {
 					blocked, reason, vulnErr := m.scanner.CheckVulnerabilities(ctx, registry, name, version)
 					if vulnErr != nil {
 						log.Warn().Err(vulnErr).Str("package", name).Msg("Failed to check vulnerabilities")
@@ -293,17 +318,22 @@ func (m *Manager) getOrFetch(ctx context.Context, registry, name, version string
 	log.Debug().Str("package", name).Str("version", version).Msg("Fetching from upstream")
 
 	// Fetch from upstream
-	data, upstreamURL, err := fetchFunc(ctx)
+	fr, err := fetchFunc(ctx)
 	if err != nil {
 		metrics.RecordUpstreamRequest(registry, "error")
 		return nil, errors.Wrap(err, errors.ErrCodeUpstreamFailure, "failed to fetch from upstream")
 	}
+	if fr == nil || fr.Data == nil {
+		return nil, errors.New(errors.ErrCodeUpstreamFailure, "upstream fetch returned no data")
+	}
+	data := fr.Data
 	defer func() { _ = data.Close() }() // #nosec G104 -- Cleanup, error not critical
 
 	metrics.RecordUpstreamRequest(registry, "success")
 
-	// Store in cache (this will also trigger background scan)
-	storedPkg, err := m.store(ctx, registry, name, version, data, upstreamURL)
+	// Store in cache (this will also trigger background scan). Auth state is
+	// plumbed through so the persisted package carries RequiresAuth.
+	storedPkg, err := m.store(ctx, registry, name, version, data, fr.UpstreamURL, fr.RequiresAuth, fr.AuthProvider)
 	if err != nil {
 		return nil, err
 	}
@@ -412,45 +442,56 @@ func (m *Manager) getOrFetch(ctx context.Context, registry, name, version string
 	// Data is intentionally nil; Get() opens a fresh reader per caller.
 	return &CacheEntry{
 		Package:     storedPkg,
-		Data:        nil,
+		UpstreamURL: fr.UpstreamURL,
 		FromCache:   false,
-		UpstreamURL: upstreamURL,
 	}, nil
 }
 
 // store stores a package in cache
-func (m *Manager) store(ctx context.Context, registry, name, version string, data io.ReadCloser, upstreamURL string) (*metadata.Package, error) {
+func (m *Manager) store(ctx context.Context, registry, name, version string, data io.ReadCloser, upstreamURL string, requiresAuth bool, authProvider string) (*metadata.Package, error) {
 	// Generate storage key
 	storageKey := m.generateStorageKey(registry, name, version)
 
-	// Calculate checksums while storing
-	// We need to read the data, calculate checksums, and store it
-	// This requires buffering the data
-	var buf []byte
-	var err error
-
-	// Cap upstream read to MaxPackageSize to prevent OOM on hostile/oversized
-	// upstream responses. Read one extra byte so we can detect overflow.
+	// Stream upstream to a temp file while computing checksums, instead of
+	// buffering the full payload in memory (avoids OOM on large packages,
+	// e.g. the default 2 GB MaxPackageSize). The temp file also becomes the
+	// scan source for backends that can't expose a local path, so the payload
+	// is never held twice in RAM.
 	maxSize := m.config.MaxPackageSize
 	if maxSize <= 0 {
 		maxSize = 2 * 1024 * 1024 * 1024 // 2GB safety floor
 	}
-	limited := io.LimitReader(data, maxSize+1)
-	buf, err = io.ReadAll(limited)
+
+	tempFile, err := os.CreateTemp(os.TempDir(), "gohoarder-store-*")
 	if err != nil {
+		return nil, errors.Wrap(err, errors.ErrCodeUpstreamFailure, "failed to create temp file for upstream data")
+	}
+	tempPath := tempFile.Name()
+	// Temp file is removed when store() returns, unless ownership is handed
+	// to a scan goroutine (remote backends reuse it for scanning).
+	scanOwnsTemp := false
+	defer func() {
+		if !scanOwnsTemp {
+			_ = os.Remove(tempPath) // #nosec G104 -- cleanup
+		}
+	}()
+
+	// Compute SHA256 as the payload is streamed to the temp file. Cap at
+	// maxSize+1 so we can detect overflow without reading unbounded data.
+	hash := sha256.New()
+	limited := io.LimitReader(data, maxSize+1)
+	written, err := io.Copy(io.MultiWriter(tempFile, hash), limited)
+	if err != nil {
+		_ = tempFile.Close() // #nosec G104 -- cleanup
 		return nil, errors.Wrap(err, errors.ErrCodeUpstreamFailure, "failed to read upstream data")
 	}
-	if int64(len(buf)) > maxSize {
+	if written > maxSize {
+		_ = tempFile.Close() // #nosec G104 -- cleanup
 		return nil, errors.New(errors.ErrCodePayloadTooLarge,
 			fmt.Sprintf("upstream package exceeds max size (%d bytes)", maxSize))
 	}
-
-	// Calculate checksums
-	h := sha256.New()
-	h.Write(buf)
-	checksumSHA256 := fmt.Sprintf("%x", h.Sum(nil))
-
-	size := int64(len(buf))
+	checksumSHA256 := fmt.Sprintf("%x", hash.Sum(nil))
+	size := written
 
 	// Check quota before storing
 	quota, err := m.storage.GetQuota(ctx)
@@ -458,20 +499,28 @@ func (m *Manager) store(ctx context.Context, registry, name, version string, dat
 		if quota.Used+size > quota.Limit {
 			// Trigger eviction
 			if evictErr := m.evict(ctx, size); evictErr != nil {
+				_ = tempFile.Close() // #nosec G104 -- cleanup
 				return nil, errors.QuotaExceeded(quota.Limit)
 			}
 		}
 	}
 
+	// Seek temp file back to start and stream it to the storage backend.
+	if _, err := tempFile.Seek(0, io.SeekStart); err != nil {
+		_ = tempFile.Close() // #nosec G104 -- cleanup
+		return nil, errors.Wrap(err, errors.ErrCodeStorageFailure, "failed to seek temp file")
+	}
+
 	// Store in storage backend
 	opts := &storage.PutOptions{
 		ChecksumSHA256: checksumSHA256,
 	}
 
-	err = m.storage.Put(ctx, storageKey, io.NopCloser(bytes.NewReader(buf)), opts)
-	if err != nil {
+	if err := m.storage.Put(ctx, storageKey, tempFile, opts); err != nil {
+		_ = tempFile.Close() // #nosec G104 -- cleanup
 		return nil, err
 	}
+	_ = tempFile.Close() // #nosec G104 -- cleanup; scan may still read the file
 
 	// Create metadata entry
 	now := time.Now()
@@ -486,6 +535,8 @@ func (m *Manager) store(ctx context.Context, registry, name, version string, dat
 		Size:           size,
 		ChecksumSHA256: checksumSHA256,
 		UpstreamURL:    upstreamURL,
+		RequiresAuth:   requiresAuth,
+		AuthProvider:   authProvider,
 		CachedAt:       now,
 		LastAccessed:   now,
 		ExpiresAt:      &expiresAt,
@@ -531,6 +582,16 @@ func (m *Manager) store(ctx context.Context, registry, name, version string, dat
 	// Scan package if scanner is enabled (run in background to not block cache operations)
 	// Skip scanning metadata entries (index pages, lists, etc.)
 	if m.scanner != nil && !isMetadataEntry {
+		// Decide synchronously whether the streaming temp file must outlive
+		// store(). Remote backends (no GetLocalPath) reuse it as the scan
+		// source; local backends scan from GetLocalPath and don't need it.
+		_, hasLocalPath := m.storage.(interface {
+			GetLocalPath(ctx context.Context, key string) (string, error)
+		})
+		if !hasLocalPath {
+			scanOwnsTemp = true
+		}
+
 		go func() {
 			scanCtx := context.Background()
 			var filePath string
@@ -550,27 +611,11 @@ func (m *Manager) store(ctx context.Context, registry, name, version string, dat
 				cleanupFunc = func() {} // No cleanup needed for direct path
 				log.Debug().Str("package", name).Str("path", filePath).Msg("Scanning package from storage path")
 			} else {
-				// Fallback: Create temp file for remote storage (S3, SMB, etc.).
-				// Use os.CreateTemp so the OS picks a safe, unique filename — this
-				// prevents path traversal via storageKey containing "..".
-				tempFile, err := os.CreateTemp(os.TempDir(), "gohoarder-scan-*")
-				if err != nil {
-					log.Error().Err(err).Str("package", name).Msg("Failed to create temp file for scanning")
-					return
-				}
-				tempFilePath := tempFile.Name()
-
-				// Write package data to temp file
-				if _, err := tempFile.Write(buf); err != nil {
-					_ = tempFile.Close()        // #nosec G104 -- Cleanup, error not critical
-					_ = os.Remove(tempFilePath) // #nosec G104 -- Cleanup, error not critical
-					log.Error().Err(err).Str("package", name).Msg("Failed to write temp file for scanning")
-					return
-				}
-				_ = tempFile.Close() // #nosec G104 -- Cleanup, error not critical
-
-				filePath = tempFilePath
-				cleanupFunc = func() { _ = os.Remove(tempFilePath) } // #nosec G104 -- Cleanup
+				// Remote storage (S3, SMB, etc.) — reuse the temp file store()
+				// already wrote during streaming. This avoids re-uploading the
+				// payload into another temp file and avoids holding it in RAM.
+				filePath = tempPath
+				cleanupFunc = func() { _ = os.Remove(tempPath) } // #nosec G104 -- Cleanup
 				log.Debug().Str("package", name).Str("path", filePath).Msg("Scanning package from temp file")
 			}
 

pkg/cache/cache_test.go

@@ -355,7 +355,7 @@ func TestNew(t *testing.T) {
 func TestGet(t *testing.T) {
 	tests := []struct {
 		setupMock     func(*MockStorageBackend, *MockMetadataStore)
-		fetchFunc     func(context.Context) (io.ReadCloser, string, error)
+		fetchFunc     FetchFunc
 		name          string
 		registry      string
 		packageName   string
@@ -404,8 +404,8 @@ func TestGet(t *testing.T) {
 				s.On("Get", mock.Anything, "npm/lodash/4.17.21").Return(io.NopCloser(strings.NewReader("upstream data")), nil)
 				m.On("UpdateDownloadCount", mock.Anything, "npm", "lodash", "4.17.21").Return(nil)
 			},
-			fetchFunc: func(ctx context.Context) (io.ReadCloser, string, error) {
-				return io.NopCloser(strings.NewReader("upstream data")), "https://registry.npmjs.org/lodash", nil
+			fetchFunc: func(ctx context.Context) (*FetchResult, error) {
+				return &FetchResult{Data: io.NopCloser(strings.NewReader("upstream data")), UpstreamURL: "https://registry.npmjs.org/lodash"}, nil
 			},
 			wantFromCache: false,
 			wantErr:       false,
@@ -436,8 +436,8 @@ func TestGet(t *testing.T) {
 				s.On("Get", mock.Anything, "npm/expired-pkg/1.0.0").Return(io.NopCloser(strings.NewReader("refreshed data")), nil)
 				m.On("UpdateDownloadCount", mock.Anything, "npm", "expired-pkg", "1.0.0").Return(nil)
 			},
-			fetchFunc: func(ctx context.Context) (io.ReadCloser, string, error) {
-				return io.NopCloser(strings.NewReader("refreshed data")), "https://registry.npmjs.org/expired-pkg", nil
+			fetchFunc: func(ctx context.Context) (*FetchResult, error) {
+				return &FetchResult{Data: io.NopCloser(strings.NewReader("refreshed data")), UpstreamURL: "https://registry.npmjs.org/expired-pkg"}, nil
 			},
 			wantFromCache: false,
 			wantErr:       false,
@@ -464,8 +464,8 @@ func TestGet(t *testing.T) {
 			setupMock: func(s *MockStorageBackend, m *MockMetadataStore) {
 				m.On("GetPackage", mock.Anything, "npm", "fail-pkg", "1.0.0").Return(nil, errors.New("not found"))
 			},
-			fetchFunc: func(ctx context.Context) (io.ReadCloser, string, error) {
-				return nil, "", errors.New("upstream error")
+			fetchFunc: func(ctx context.Context) (*FetchResult, error) {
+				return nil, errors.New("upstream error")
 			},
 			wantErr:     true,
 			errContains: "failed to fetch from upstream",
@@ -498,8 +498,8 @@ func TestGet(t *testing.T) {
 				s.On("Get", mock.Anything, "npm/inconsistent/1.0.0").Return(io.NopCloser(strings.NewReader("recovered data")), nil).Once()
 				m.On("UpdateDownloadCount", mock.Anything, "npm", "inconsistent", "1.0.0").Return(nil)
 			},
-			fetchFunc: func(ctx context.Context) (io.ReadCloser, string, error) {
-				return io.NopCloser(strings.NewReader("recovered data")), "https://registry.npmjs.org/inconsistent", nil
+			fetchFunc: func(ctx context.Context) (*FetchResult, error) {
+				return &FetchResult{Data: io.NopCloser(strings.NewReader("recovered data")), UpstreamURL: "https://registry.npmjs.org/inconsistent"}, nil
 			},
 			wantFromCache: false,
 			wantErr:       false,
@@ -515,8 +515,8 @@ func TestGet(t *testing.T) {
 				s.On("GetQuota", mock.Anything).Return(&storage.QuotaInfo{Used: 100, Available: 900, Limit: 1000}, nil)
 				s.On("Put", mock.Anything, "npm/save-fail/1.0.0", mock.Anything, mock.Anything).Return(errors.New("storage error"))
 			},
-			fetchFunc: func(ctx context.Context) (io.ReadCloser, string, error) {
-				return io.NopCloser(strings.NewReader("data")), "https://registry.npmjs.org/save-fail", nil
+			fetchFunc: func(ctx context.Context) (*FetchResult, error) {
+				return &FetchResult{Data: io.NopCloser(strings.NewReader("data")), UpstreamURL: "https://registry.npmjs.org/save-fail"}, nil
 			},
 			wantErr:     true,
 			errContains: "storage error",
@@ -534,8 +534,8 @@ func TestGet(t *testing.T) {
 				m.On("SavePackage", mock.Anything, mock.Anything).Return(errors.New("metadata error"))
 				s.On("Delete", mock.Anything, "npm/meta-fail/1.0.0").Return(nil)
 			},
-			fetchFunc: func(ctx context.Context) (io.ReadCloser, string, error) {
-				return io.NopCloser(strings.NewReader("data")), "https://registry.npmjs.org/meta-fail", nil
+			fetchFunc: func(ctx context.Context) (*FetchResult, error) {
+				return &FetchResult{Data: io.NopCloser(strings.NewReader("data")), UpstreamURL: "https://registry.npmjs.org/meta-fail"}, nil
 			},
 			wantErr:     true,
 			errContains: "metadata error",
@@ -1105,8 +1105,8 @@ func TestBroadcaster_CacheMissStore(t *testing.T) {
 	bc := &fakeBroadcaster{}
 	manager.SetBroadcaster(bc)
 
-	fetch := func(ctx context.Context) (io.ReadCloser, string, error) {
-		return io.NopCloser(strings.NewReader("upstream data")), "https://registry.npmjs.org/lodash", nil
+	fetch := func(ctx context.Context) (*FetchResult, error) {
+		return &FetchResult{Data: io.NopCloser(strings.NewReader("upstream data")), UpstreamURL: "https://registry.npmjs.org/lodash"}, nil
 	}
 	entry, err := manager.Get(context.Background(), "npm", "lodash", "4.17.21", fetch)
 	require.NoError(t, err)
@@ -1153,8 +1153,8 @@ func TestBroadcaster_NoEmitOnError(t *testing.T) {
 		bc := &fakeBroadcaster{}
 		manager.SetBroadcaster(bc)
 
-		fetch := func(ctx context.Context) (io.ReadCloser, string, error) {
-			return io.NopCloser(strings.NewReader("data")), "https://registry.npmjs.org/fail", nil
+		fetch := func(ctx context.Context) (*FetchResult, error) {
+			return &FetchResult{Data: io.NopCloser(strings.NewReader("data")), UpstreamURL: "https://registry.npmjs.org/fail"}, nil
 		}
 		_, err = manager.Get(context.Background(), "npm", "fail", "1.0.0", fetch)
 		require.Error(t, err)
@@ -1178,8 +1178,8 @@ func TestBroadcaster_NoEmitOnError(t *testing.T) {
 		bc := &fakeBroadcaster{}
 		manager.SetBroadcaster(bc)
 
-		fetch := func(ctx context.Context) (io.ReadCloser, string, error) {
-			return io.NopCloser(strings.NewReader("data")), "https://registry.npmjs.org/meta-fail", nil
+		fetch := func(ctx context.Context) (*FetchResult, error) {
+			return &FetchResult{Data: io.NopCloser(strings.NewReader("data")), UpstreamURL: "https://registry.npmjs.org/meta-fail"}, nil
 		}
 		_, err = manager.Get(context.Background(), "npm", "meta-fail", "1.0.0", fetch)
 		require.Error(t, err)

pkg/config/config.go

@@ -362,6 +362,16 @@ func Default() *Config {
 		Security: SecurityConfig{
 			Enabled:         false,
 			BlockOnSeverity: "high",
+			// Default all severity caps to unlimited (-1) so the operator's
+			// BlockOnSeverity decision governs by default. A zero cap means
+			// "block any", which would make a single LOW vulnerability block
+			// every package even though the configured default is "high".
+			BlockThresholds: VulnerabilityThresholds{
+				Critical: -1,
+				High:     -1,
+				Medium:   -1,
+				Low:      -1,
+			},
 			Scanners: ScannersConfig{
 				Trivy: TrivyConfig{
 					Enabled: false,

pkg/metadata/gormstore/gormstore_v2.go

@@ -265,8 +265,22 @@ func (s *GORMStoreV2) SavePackage(ctx context.Context, pkg *metadata.Package) er
 			return errors.Wrap(result.Error, errors.ErrCodeStorageFailure, "failed to update package")
 		}
 
-		// If no rows were updated, create new record
+		// If no rows were updated, create new record.
+		// RowsAffected == 0 here means no LIVE row matches the key, because
+		// GORM's default scope appends `deleted_at IS NULL` to the UPDATE.
+		// The only possible match is a soft-deleted row (e.g. after TTL/evict
+		// called DeletePackage). That retained row still holds the same
+		// `storage_key`, which has a UNIQUE index, so a plain Create would
+		// collide (UNIQUE constraint failed: packages.storage_key) and the
+		// re-fetch would permanently 502. Hard-delete any such stale row
+		// before creating.
 		if result.RowsAffected == 0 {
+			if err := tx.Unscoped().
+				Where("registry_id = ? AND name = ? AND version = ?", registryID, pkg.Name, pkg.Version).
+				Delete(&PackageModel{}).Error; err != nil {
+				return errors.Wrap(err, errors.ErrCodeStorageFailure, "failed to purge stale soft-deleted package before create")
+			}
+
 			if err := tx.Create(model).Error; err != nil {
 				return errors.Wrap(err, errors.ErrCodeStorageFailure, "failed to create package")
 			}

pkg/metadata/gormstore/gormstore_v2_test.go

@@ -209,6 +209,57 @@ func (s *GORMStoreV2TestSuite) Test_V2_DeletePackage_Success() {
 	s.Equal(int64(1), count) // Still in DB, just soft deleted
 }
 
+// Test_V2_SavePackage_AfterSoftDelete tests that saving the same
+// registry/name/version key after a soft delete (e.g. TTL expiry or
+// cache eviction) succeeds instead of colliding on the retained
+// storage_key UNIQUE index. Regression for the permanent 502 on
+// re-fetch of a once-evicted package.
+func (s *GORMStoreV2TestSuite) Test_V2_SavePackage_AfterSoftDelete() {
+	pkg := &metadata.Package{
+		Registry:     "npm",
+		Name:         "re-add-test",
+		Version:      "1.0.0",
+		StorageKey:   "npm/re-add-test/1.0.0.tgz",
+		Size:         1000,
+		CachedAt:     time.Now(),
+		LastAccessed: time.Now(),
+	}
+	err := s.store.SavePackage(s.ctx, pkg)
+	s.NoError(err)
+
+	// Soft-delete (simulates TTL expiry / eviction)
+	err = s.store.DeletePackage(s.ctx, "npm", "re-add-test", "1.0.0")
+	s.NoError(err)
+
+	// Re-save the same key (simulates re-fetch after cache miss).
+	// Before the fix this failed with:
+	//   UNIQUE constraint failed: packages.storage_key
+	pkg2 := &metadata.Package{
+		Registry:     "npm",
+		Name:         "re-add-test",
+		Version:      "1.0.0",
+		StorageKey:   "npm/re-add-test/1.0.0.tgz",
+		Size:         2000,
+		CachedAt:     time.Now(),
+		LastAccessed: time.Now(),
+	}
+	err = s.store.SavePackage(s.ctx, pkg2)
+	s.NoError(err)
+
+	// The re-saved package must be retrievable
+	retrieved, err := s.store.GetPackage(s.ctx, "npm", "re-add-test", "1.0.0")
+	s.NoError(err)
+	s.NotNil(retrieved)
+	s.Equal(int64(2000), retrieved.Size)
+
+	// No duplicate rows retained after the hard purge
+	var count int64
+	s.store.db.Unscoped().Model(&PackageModel{}).
+		Where("name = ?", "re-add-test").
+		Count(&count)
+	s.Equal(int64(1), count)
+}
+
 // Test_V2_ListPackages_All tests listing all packages
 func (s *GORMStoreV2TestSuite) Test_V2_ListPackages_All() {
 	// Create multiple packages

pkg/network/client.go

@@ -229,19 +229,12 @@ func (c *Client) do(ctx context.Context, req *http.Request) (*http.Response, err
 		resp, err := c.client.Do(req)
 		if err != nil {
 			lastErr = err
-			if c.circuitBreaker != nil {
-				c.circuitBreaker.RecordFailure()
-			}
 			continue
 		}
-
 		// Check if response is retryable
 		if c.isRetryable(resp.StatusCode) {
 			_ = resp.Body.Close() // #nosec G104 -- Cleanup, error not critical
 			lastErr = fmt.Errorf("received retryable status code: %d", resp.StatusCode)
-			if c.circuitBreaker != nil {
-				c.circuitBreaker.RecordFailure()
-			}
 			continue
 		}
 

pkg/network/client_test.go

@@ -405,3 +405,38 @@ func TestConcurrentRequests(t *testing.T) {
 		assert.NoError(t, err)
 	}
 }
+
+// TestCircuitBreakerOpens verifies that a configured number of consecutive
+// failed requests opens the circuit breaker and that subsequent requests are
+// rejected with the circuit-open error until the breaker half-open window
+// elapses and a request succeeds again.
+func TestCircuitBreakerOpens(t *testing.T) {
+	server := httptest.NewServer(http.HandlerFunc(func(w http.ResponseWriter, r *http.Request) {
+		w.WriteHeader(http.StatusInternalServerError)
+	}))
+	defer server.Close() // #nosec G104 -- Cleanup, error not critical
+
+	client := network.NewClient(network.Config{
+		Timeout:    5 * time.Second,
+		MaxRetries: 0,
+		CircuitBreaker: network.CircuitBreakerConfig{
+			Enabled:          true,
+			FailureThreshold: 3,
+			SuccessThreshold: 1,
+			Timeout:          time.Hour,
+		},
+	})
+
+	ctx := context.Background()
+
+	// Three consecutive failed requests open the breaker.
+	for i := 0; i < 3; i++ {
+		_, _, err := client.Get(ctx, server.URL, nil)
+		assert.Error(t, err)
+	}
+
+	// The next request is rejected because the breaker is open.
+	_, _, err := client.Get(ctx, server.URL, nil)
+	assert.Error(t, err)
+	assert.Contains(t, err.Error(), "circuit breaker is open")
+}

pkg/proxy/goproxy/goproxy.go

@@ -115,7 +115,7 @@ func (h *Handler) handleList(ctx context.Context, w http.ResponseWriter, r *http
 	// Extract credentials from request
 	credentials := h.credExtractor.Extract(r)
 
-	entry, err := h.cache.Get(ctx, "go", modulePath, "list", func(ctx context.Context) (io.ReadCloser, string, error) {
+	entry, err := h.cache.Get(ctx, "go", modulePath, "list", func(ctx context.Context) (*cache.FetchResult, error) {
 		// Prepare headers for upstream request
 		headers := make(map[string]string)
 		if credentials != "" {
@@ -124,13 +124,16 @@ func (h *Handler) handleList(ctx context.Context, w http.ResponseWriter, r *http
 
 		body, statusCode, err := h.client.Get(ctx, url, headers)
 		if err != nil {
-			return nil, "", err
+			return nil, err
+		}
+		if statusCode == http.StatusUnauthorized || statusCode == http.StatusForbidden {
+			return &cache.FetchResult{Data: body, UpstreamURL: url, RequiresAuth: true, AuthProvider: h.credValidator.ProviderFor(modulePath)}, nil
 		}
 		if statusCode != http.StatusOK {
 			_ = body.Close() // #nosec G104 -- Cleanup, error not critical
-			return nil, "", fmt.Errorf("upstream returned status %d", statusCode)
+			return nil, fmt.Errorf("upstream returned status %d", statusCode)
 		}
-		return body, url, nil
+		return &cache.FetchResult{Data: body, UpstreamURL: url}, nil
 	})
 
 	if err != nil {
@@ -155,7 +158,7 @@ func (h *Handler) handleInfo(ctx context.Context, w http.ResponseWriter, r *http
 	// Extract credentials from request
 	credentials := h.credExtractor.Extract(r)
 
-	entry, err := h.cache.Get(ctx, "go", cacheKey, version, func(ctx context.Context) (io.ReadCloser, string, error) {
+	entry, err := h.cache.Get(ctx, "go", cacheKey, version, func(ctx context.Context) (*cache.FetchResult, error) {
 		// Prepare headers for upstream request
 		headers := make(map[string]string)
 		if credentials != "" {
@@ -164,13 +167,16 @@ func (h *Handler) handleInfo(ctx context.Context, w http.ResponseWriter, r *http
 
 		body, statusCode, err := h.client.Get(ctx, url, headers)
 		if err != nil {
-			return nil, "", err
+			return nil, err
+		}
+		if statusCode == http.StatusUnauthorized || statusCode == http.StatusForbidden {
+			return &cache.FetchResult{Data: body, UpstreamURL: url, RequiresAuth: true, AuthProvider: h.credValidator.ProviderFor(modulePath)}, nil
 		}
 		if statusCode != http.StatusOK {
 			_ = body.Close() // #nosec G104 -- Cleanup, error not critical
-			return nil, "", fmt.Errorf("upstream returned status %d", statusCode)
+			return nil, fmt.Errorf("upstream returned status %d", statusCode)
 		}
-		return body, url, nil
+		return &cache.FetchResult{Data: body, UpstreamURL: url}, nil
 	})
 
 	if err != nil {
@@ -188,14 +194,14 @@ func (h *Handler) handleInfo(ctx context.Context, w http.ResponseWriter, r *http
 func (h *Handler) handleMod(ctx context.Context, w http.ResponseWriter, r *http.Request, path string) {
 	url := h.upstream + path
 	modulePath := h.extractModulePath(path)
+
+	// Extract credentials from request
+	credentials := h.credExtractor.Extract(r)
 	version := h.extractVersion(path, ".mod")
 	// Use .mod suffix to distinguish from .info and .zip in cache
 	cacheKey := modulePath + "/@v/" + version + ".mod"
 
-	// Extract credentials from request
-	credentials := h.credExtractor.Extract(r)
-
-	entry, err := h.cache.Get(ctx, "go", cacheKey, version, func(ctx context.Context) (io.ReadCloser, string, error) {
+	entry, err := h.cache.Get(ctx, "go", cacheKey, version, func(ctx context.Context) (*cache.FetchResult, error) {
 		// Prepare headers for upstream request
 		headers := make(map[string]string)
 		if credentials != "" {
@@ -204,13 +210,16 @@ func (h *Handler) handleMod(ctx context.Context, w http.ResponseWriter, r *http.
 
 		body, statusCode, err := h.client.Get(ctx, url, headers)
 		if err != nil {
-			return nil, "", err
+			return nil, err
+		}
+		if statusCode == http.StatusUnauthorized || statusCode == http.StatusForbidden {
+			return &cache.FetchResult{Data: body, UpstreamURL: url, RequiresAuth: true, AuthProvider: h.credValidator.ProviderFor(modulePath)}, nil
 		}
 		if statusCode != http.StatusOK {
 			_ = body.Close() // #nosec G104 -- Cleanup, error not critical
-			return nil, "", fmt.Errorf("upstream returned status %d", statusCode)
+			return nil, fmt.Errorf("upstream returned status %d", statusCode)
 		}
-		return body, url, nil
+		return &cache.FetchResult{Data: body, UpstreamURL: url}, nil
 	})
 
 	if err != nil {
@@ -245,7 +254,7 @@ func (h *Handler) handleZip(ctx context.Context, w http.ResponseWriter, r *http.
 		Bool("has_credentials", credentials != "").
 		Msg("Handling Go module zip request")
 
-	entry, err := h.cache.Get(ctx, "go", cacheKey, version, func(ctx context.Context) (io.ReadCloser, string, error) {
+	entry, err := h.cache.Get(ctx, "go", cacheKey, version, func(ctx context.Context) (*cache.FetchResult, error) {
 		// Prepare headers for upstream request
 		headers := make(map[string]string)
 		if credentials != "" {
@@ -255,7 +264,7 @@ func (h *Handler) handleZip(ctx context.Context, w http.ResponseWriter, r *http.
 		// Try upstream proxy first (fast path for public modules)
 		body, statusCode, err := h.client.Get(ctx, url, headers)
 		if err == nil && statusCode == http.StatusOK {
-			return body, url, nil
+			return &cache.FetchResult{Data: body, UpstreamURL: url}, nil
 		}
 
 		// If upstream failed with 404 or 403, try git fallback (private modules)
@@ -278,9 +287,9 @@ func (h *Handler) handleZip(ctx context.Context, w http.ResponseWriter, r *http.
 			_ = body.Close() // #nosec G104 -- Cleanup, error not critical
 		}
 		if err != nil {
-			return nil, "", err
+			return nil, err
 		}
-		return nil, "", fmt.Errorf("upstream returned status %d", statusCode)
+		return nil, fmt.Errorf("upstream returned status %d", statusCode)
 	})
 
 	if err != nil {
@@ -299,6 +308,10 @@ func (h *Handler) handleZip(ctx context.Context, w http.ResponseWriter, r *http.
 	defer func() { _ = entry.Data.Close() }() // #nosec G104 -- Cleanup, error not critical
 
 	// CRITICAL SECURITY CHECK: If module requires auth, validate credentials
+	// The auth validation cache is owned by this handler instance only, so its
+	// key may use the module path (modulePath) rather than a URL. The module path
+	// uniquely identifies the private module within this registry's cache; there
+	// is no cross-registry collision because npm/pypi use their own instances.
 	if entry.Package != nil && entry.Package.RequiresAuth {
 		// Check validation cache first
 		allowed, cached, reason := h.validationCache.Get(credHash, modulePath)
@@ -352,6 +365,7 @@ func (h *Handler) handleZip(ctx context.Context, w http.ResponseWriter, r *http.
 
 	w.Header().Set("Content-Type", "application/zip")
 	_, _ = io.Copy(w, entry.Data) // #nosec G104 -- HTTP response write
+
 }
 
 // handleLatest handles /@latest requests
@@ -362,7 +376,7 @@ func (h *Handler) handleLatest(ctx context.Context, w http.ResponseWriter, r *ht
 	// Extract credentials from request
 	credentials := h.credExtractor.Extract(r)
 
-	entry, err := h.cache.Get(ctx, "go", modulePath, "latest", func(ctx context.Context) (io.ReadCloser, string, error) {
+	entry, err := h.cache.Get(ctx, "go", modulePath, "latest", func(ctx context.Context) (*cache.FetchResult, error) {
 		// Prepare headers for upstream request
 		headers := make(map[string]string)
 		if credentials != "" {
@@ -371,13 +385,16 @@ func (h *Handler) handleLatest(ctx context.Context, w http.ResponseWriter, r *ht
 
 		body, statusCode, err := h.client.Get(ctx, url, headers)
 		if err != nil {
-			return nil, "", err
+			return nil, err
+		}
+		if statusCode == http.StatusUnauthorized || statusCode == http.StatusForbidden {
+			return &cache.FetchResult{Data: body, UpstreamURL: url, RequiresAuth: true, AuthProvider: h.credValidator.ProviderFor(modulePath)}, nil
 		}
 		if statusCode != http.StatusOK {
 			_ = body.Close() // #nosec G104 -- Cleanup, error not critical
-			return nil, "", fmt.Errorf("upstream returned status %d", statusCode)
+			return nil, fmt.Errorf("upstream returned status %d", statusCode)
 		}
-		return body, url, nil
+		return &cache.FetchResult{Data: body, UpstreamURL: url}, nil
 	})
 
 	if err != nil {
@@ -450,7 +467,7 @@ func (h *Handler) extractModulePath(path string) string {
 }
 
 // fetchModuleFromGit fetches a Go module directly from git repository
-func (h *Handler) fetchModuleFromGit(ctx context.Context, modulePath, version, credentials string) (io.ReadCloser, string, error) {
+func (h *Handler) fetchModuleFromGit(ctx context.Context, modulePath, version, credentials string) (*cache.FetchResult, error) {
 	log.Info().
 		Str("module", modulePath).
 		Str("version", version).
@@ -459,23 +476,25 @@ func (h *Handler) fetchModuleFromGit(ctx context.Context, modulePath, version, c
 	// 1. Fetch module source from git
 	srcPath, err := h.gitFetcher.FetchModule(ctx, modulePath, version, credentials)
 	if err != nil {
-		return nil, "", fmt.Errorf("git fetch failed: %w", err)
+		return nil, fmt.Errorf("git fetch failed: %w", err)
 	}
 	defer h.gitFetcher.Cleanup(srcPath)
 
 	// 2. Validate module
 	if validateErr := h.moduleBuilder.ValidateModule(ctx, srcPath, modulePath); validateErr != nil {
-		return nil, "", fmt.Errorf("module validation failed: %w", validateErr)
+		return nil, fmt.Errorf("module validation failed: %w", validateErr)
 	}
 
 	// 3. Build module zip
 	zipReader, err := h.moduleBuilder.BuildModuleZip(ctx, srcPath, modulePath, version)
 	if err != nil {
-		return nil, "", fmt.Errorf("module zip build failed: %w", err)
+		return nil, fmt.Errorf("module zip build failed: %w", err)
 	}
 
-	// Create source URL for logging
-	sourceURL := fmt.Sprintf("git+https://%s@%s", modulePath, version)
+	// Create source URL for logging. Private modules fetched from git require
+	// auth, so mark the result accordingly. FIX-L3: strip the git+ scheme so the
+	// stored UpstreamURL is a fetchable HTTPS URL.
+	sourceURL := fmt.Sprintf("https://%s@%s", modulePath, version)
 
 	log.Info().
 		Str("module", modulePath).
@@ -483,5 +502,10 @@ func (h *Handler) fetchModuleFromGit(ctx context.Context, modulePath, version, c
 		Str("source", sourceURL).
 		Msg("Successfully built module from git")
 
-	return zipReader, sourceURL, nil
+	return &cache.FetchResult{
+		Data:         zipReader,
+		UpstreamURL:  sourceURL,
+		RequiresAuth: true,
+		AuthProvider: h.credValidator.ProviderFor(modulePath),
+	}, nil
 }

pkg/proxy/npm/npm.go

@@ -80,16 +80,19 @@ func (h *Handler) handleMetadata(ctx context.Context, w http.ResponseWriter, r *
 	url := h.upstream + path
 	packageName := extractPackageName(path)
 
-	entry, err := h.cache.Get(ctx, "npm", packageName, "metadata", func(ctx context.Context) (io.ReadCloser, string, error) {
+	entry, err := h.cache.Get(ctx, "npm", packageName, "metadata", func(ctx context.Context) (*cache.FetchResult, error) {
 		body, statusCode, fetchErr := h.client.Get(ctx, url, nil)
 		if fetchErr != nil {
-			return nil, "", fetchErr
+			return nil, fetchErr
+		}
+		if statusCode == http.StatusUnauthorized || statusCode == http.StatusForbidden {
+			return &cache.FetchResult{Data: body, UpstreamURL: url, RequiresAuth: true, AuthProvider: h.credValidator.Provider()}, nil
 		}
 		if statusCode != http.StatusOK {
 			_ = body.Close()
-			return nil, "", fmt.Errorf("upstream returned status %d", statusCode)
+			return nil, fmt.Errorf("upstream returned status %d", statusCode)
 		}
-		return body, url, nil
+		return &cache.FetchResult{Data: body, UpstreamURL: url}, nil
 	})
 
 	if err != nil {
@@ -158,9 +161,7 @@ func (h *Handler) handleTarball(ctx context.Context, w http.ResponseWriter, r *h
 		Str("cred_hash", credHash).
 		Bool("has_credentials", credentials != "").
 		Msg("Handling tarball request")
-
-	// Try to get from cache first (with credential-aware key)
-	entry, err := h.cache.Get(ctx, "npm", packageName, version, func(ctx context.Context) (io.ReadCloser, string, error) {
+	entry, err := h.cache.Get(ctx, "npm", packageName, version, func(ctx context.Context) (*cache.FetchResult, error) {
 		// Prepare headers for upstream request
 		headers := make(map[string]string)
 		if credentials != "" {
@@ -169,13 +170,16 @@ func (h *Handler) handleTarball(ctx context.Context, w http.ResponseWriter, r *h
 
 		body, statusCode, fetchErr := h.client.Get(ctx, url, headers)
 		if fetchErr != nil {
-			return nil, "", fetchErr
+			return nil, fetchErr
+		}
+		if statusCode == http.StatusUnauthorized || statusCode == http.StatusForbidden {
+			return &cache.FetchResult{Data: body, UpstreamURL: url, RequiresAuth: true, AuthProvider: h.credValidator.Provider()}, nil
 		}
 		if statusCode != http.StatusOK {
 			_ = body.Close()
-			return nil, "", fmt.Errorf("upstream returned status %d", statusCode)
+			return nil, fmt.Errorf("upstream returned status %d", statusCode)
 		}
-		return body, url, nil
+		return &cache.FetchResult{Data: body, UpstreamURL: url}, nil
 	})
 
 	if err != nil {
@@ -198,6 +202,10 @@ func (h *Handler) handleTarball(ctx context.Context, w http.ResponseWriter, r *h
 	}()
 
 	// CRITICAL SECURITY CHECK: If package requires auth, validate credentials
+	// The validation cache is owned by this handler instance only, so the key
+	// uses the upstream tarball URL. Uniquely identifies the artifact within
+	// this registry; no cross-registry collision (goproxy/pypi keep their own
+	// independent instances).
 	if entry.Package != nil && entry.Package.RequiresAuth {
 		// Check validation cache first
 		allowed, cached, reason := h.validationCache.Get(credHash, url)

pkg/proxy/pypi/pypi.go

@@ -124,16 +124,19 @@ func (h *Handler) ServeHTTP(w http.ResponseWriter, r *http.Request) {
 func (h *Handler) handleIndex(ctx context.Context, w http.ResponseWriter, r *http.Request) {
 	url := h.upstream + "/"
 
-	entry, err := h.cache.Get(ctx, "pypi", "index", "latest", func(ctx context.Context) (io.ReadCloser, string, error) {
+	entry, err := h.cache.Get(ctx, "pypi", "index", "latest", func(ctx context.Context) (*cache.FetchResult, error) {
 		body, statusCode, err := h.client.Get(ctx, url, nil)
 		if err != nil {
-			return nil, "", err
+			return nil, err
+		}
+		if statusCode == http.StatusUnauthorized || statusCode == http.StatusForbidden {
+			return &cache.FetchResult{Data: body, UpstreamURL: url, RequiresAuth: true, AuthProvider: h.credValidator.Provider()}, nil
 		}
 		if statusCode != http.StatusOK {
 			_ = body.Close()
-			return nil, "", fmt.Errorf("upstream returned status %d", statusCode)
+			return nil, fmt.Errorf("upstream returned status %d", statusCode)
 		}
-		return body, url, nil
+		return &cache.FetchResult{Data: body, UpstreamURL: url}, nil
 	})
 
 	if err != nil {
@@ -155,17 +158,19 @@ func (h *Handler) handleIndex(ctx context.Context, w http.ResponseWriter, r *htt
 func (h *Handler) handlePackagePage(ctx context.Context, w http.ResponseWriter, r *http.Request, path string) {
 	url := h.upstream + path
 	packageName := extractPackageName(path)
-
-	entry, err := h.cache.Get(ctx, "pypi", packageName, "page", func(ctx context.Context) (io.ReadCloser, string, error) {
+	entry, err := h.cache.Get(ctx, "pypi", packageName, "page", func(ctx context.Context) (*cache.FetchResult, error) {
 		body, statusCode, err := h.client.Get(ctx, url, nil)
 		if err != nil {
-			return nil, "", err
+			return nil, err
+		}
+		if statusCode == http.StatusUnauthorized || statusCode == http.StatusForbidden {
+			return &cache.FetchResult{Data: body, UpstreamURL: url, RequiresAuth: true, AuthProvider: h.credValidator.Provider()}, nil
 		}
 		if statusCode != http.StatusOK {
 			_ = body.Close()
-			return nil, "", fmt.Errorf("upstream returned status %d", statusCode)
+			return nil, fmt.Errorf("upstream returned status %d", statusCode)
 		}
-		return body, url, nil
+		return &cache.FetchResult{Data: body, UpstreamURL: url}, nil
 	})
 
 	if err != nil {
@@ -199,16 +204,17 @@ func (h *Handler) handlePackagePage(ctx context.Context, w http.ResponseWriter,
 func (h *Handler) handlePackageFile(ctx context.Context, w http.ResponseWriter, r *http.Request, path string) {
 	packageName, version := extractPackageFileInfo(path)
 
-	// Make version unique by appending file type to avoid cache collisions
-	// between .whl and .metadata files with same version
-	cacheVersion := version
-	if strings.HasSuffix(path, ".metadata") {
-		cacheVersion = version + ".metadata"
-	} else if strings.HasSuffix(path, ".whl") {
-		cacheVersion = version + ".whl"
-	} else if strings.HasSuffix(path, ".tar.gz") {
-		cacheVersion = version + ".tar.gz"
+	// cacheVersion is the cache key's version portion. It must be unique per
+	// distinct artifact. PyPI publishes many files per release (multiple
+	// wheels with different build tags, sdists, zips, .egg files, and
+	// .metadata files for PEP 658), so the bare version is too coarse:
+	// distinct files of the same version would collide on the same cache
+	// key. The full unique basename guarantees one cache entry per artifact.
+	filename := path
+	if i := strings.LastIndex(filename, "/"); i >= 0 {
+		filename = filename[i+1:]
 	}
+	cacheVersion := filename
 
 	// Extract credentials from request
 	credentials := h.credExtractor.Extract(r)
@@ -255,7 +261,7 @@ func (h *Handler) handlePackageFile(ctx context.Context, w http.ResponseWriter,
 		Bool("has_credentials", credentials != "").
 		Msg("Handling PyPI package file request")
 
-	entry, err := h.cache.Get(ctx, "pypi", packageName, cacheVersion, func(ctx context.Context) (io.ReadCloser, string, error) {
+	entry, err := h.cache.Get(ctx, "pypi", packageName, cacheVersion, func(ctx context.Context) (*cache.FetchResult, error) {
 		// Prepare headers for upstream request
 		headers := make(map[string]string)
 		if credentials != "" {
@@ -264,13 +270,16 @@ func (h *Handler) handlePackageFile(ctx context.Context, w http.ResponseWriter,
 
 		body, statusCode, err := h.client.Get(ctx, originalURL, headers)
 		if err != nil {
-			return nil, "", err
+			return nil, err
+		}
+		if statusCode == http.StatusUnauthorized || statusCode == http.StatusForbidden {
+			return &cache.FetchResult{Data: body, UpstreamURL: originalURL, RequiresAuth: true, AuthProvider: h.credValidator.Provider()}, nil
 		}
 		if statusCode != http.StatusOK {
 			_ = body.Close()
-			return nil, "", fmt.Errorf("upstream returned status %d", statusCode)
+			return nil, fmt.Errorf("upstream returned status %d", statusCode)
 		}
-		return body, originalURL, nil
+		return &cache.FetchResult{Data: body, UpstreamURL: originalURL}, nil
 	})
 
 	if err != nil {
@@ -293,6 +302,10 @@ func (h *Handler) handlePackageFile(ctx context.Context, w http.ResponseWriter,
 	}()
 
 	// CRITICAL SECURITY CHECK: If package requires auth, validate credentials
+	// The validation cache is owned by this handler instance only, so the key
+	// uses the upstream artifact URL (originalURL). Uniquely identifies the
+	// artifact within this registry; no cross-registry collision (goproxy/npm
+	// keep their own independent instances).
 	if entry.Package != nil && entry.Package.RequiresAuth {
 		// Check validation cache first
 		allowed, cached, reason := h.validationCache.Get(credHash, originalURL)
@@ -395,37 +408,60 @@ func extractPackageName(path string) string {
 func extractPackageFileInfo(path string) (string, string) {
 	// Format: /package-name/package-name-version.whl
 	// or: /package-name/package-name-version.tar.gz
-
 	packageName := extractPackageName(path)
 
-	// Extract filename
 	parts := strings.Split(path, "/")
 	if len(parts) < 2 {
 		return packageName, ""
 	}
 
-	filename := parts[len(parts)-1]
+	base := parts[len(parts)-1]
+	isWheel := strings.HasSuffix(base, ".whl")
+	base = strings.TrimSuffix(base, ".whl")
+	base = strings.TrimSuffix(base, ".tar.gz")
+	base = strings.TrimSuffix(base, ".zip")
+	base = strings.TrimSuffix(base, ".egg")
+	base = strings.TrimSuffix(base, ".metadata")
 
-	// Remove extension
-	filename = strings.TrimSuffix(filename, ".whl")
-	filename = strings.TrimSuffix(filename, ".tar.gz")
-	filename = strings.TrimSuffix(filename, ".zip")
-	filename = strings.TrimSuffix(filename, ".egg")
+	return packageName, extractVersionFromFilename(base, isWheel)
+}
 
-	// Extract version
-	// Filename format: package-name-version or package_name-version
-	// Version typically starts after last dash before build tags
-	versionParts := strings.Split(filename, "-")
-	if len(versionParts) >= 2 {
-		// Simple heuristic: version is the part that starts with a digit
-		for i := 1; i < len(versionParts); i++ {
-			if len(versionParts[i]) > 0 && versionParts[i][0] >= '0' && versionParts[i][0] <= '9' {
-				return packageName, versionParts[i]
-			}
+// extractVersionFromFilename extracts the version from a PyPI distribution
+// filename with the extension already stripped.
+//
+// Wheels (PEP 427) are formatted as
+//
+//	{distribution}-{version}(-{build})?-{python}-{abi}-{platform}
+//
+// and the distribution is normalized (lowercase, runs of '-', '.', '_'
+// collapsed to '_'), so it never contains '-' and the version is always the
+// second dash-separated segment. For sdists/zips/eggs the filename is
+// {name}-{version}; PyPI normalizes name separators to '_', so the version
+// is always the last dash-separated segment (PEP 440 versions never contain
+// '-').
+//
+// The historical first-digit-segment heuristic is avoided because it mangles
+// digit-embedded distribution names (e.g. "2captcha-1.0.0" → "2captcha") and
+// intermediate digit segments (e.g. "foo-2019bar-1.0" → "2019bar"). The last
+// digit-starting segment is correct for those cases.
+func extractVersionFromFilename(base string, isWheel bool) string {
+	if isWheel {
+		// The distribution never contains '-', so the version immediately
+		// follows the first '-'.
+		if parts := strings.SplitN(base, "-", 3); len(parts) >= 2 && parts[1] != "" && parts[1][0] >= '0' && parts[1][0] <= '9' {
+			return parts[1]
 		}
 	}
 
-	return packageName, filename
+	// Non-wheel fallback (and defensive wheel edge case): the last
+	// dash-separated segment that starts with a digit.
+	parts := strings.Split(base, "-")
+	for i := len(parts) - 1; i >= 1; i-- {
+		if len(parts[i]) > 0 && parts[i][0] >= '0' && parts[i][0] <= '9' {
+			return parts[i]
+		}
+	}
+	return base
 }
 
 // getProxyBaseURL constructs the proxy base URL from the request

pkg/proxy/pypi/pypi_test.go

@@ -4,6 +4,7 @@ import (
 	"net/http"
 	"net/http/httptest"
 	"net/url"
+	"strings"
 	"testing"
 
 	"github.com/lukaszraczylo/gohoarder/pkg/auth"
@@ -137,3 +138,72 @@ func indexOf(s, sub string) int {
 	}
 	return -1
 }
+
+func TestExtractPackageFileInfo(t *testing.T) {
+	tests := []struct {
+		name     string
+		path     string
+		wantName string
+		wantVer  string
+	}{
+		{"numpy wheel", "/numpy/numpy-1.26.0rc1-cp312-cp312-manylinux.whl", "numpy", "1.26.0rc1"},
+		{"underscore wheel name", "/typing_extensions/typing_extensions-4.8.0-py3-none-any.whl", "typing_extensions", "4.8.0"},
+		{"hyphenated sdist", "/my-pkg/my-pkg-2.0.1.tar.gz", "my-pkg", "2.0.1"},
+		{"hyphen name underscore file", "/typed-ast/typed_ast-1.5.4.tar.gz", "typed-ast", "1.5.4"},
+		{"digit-embedded name", "/2captcha/2captcha-1.0.0.tar.gz", "2captcha", "1.0.0"},
+		{"digit intermediate segment", "/foo/foo-2019bar-1.0.zip", "foo", "1.0"},
+		{"egg file", "/foo/foo-1.0.egg", "foo", "1.0"},
+		{"metadata file", "/foo/foo-1.0.metadata", "foo", "1.0"},
+		{"no version", "/foo", "foo", "foo"},
+	}
+
+	for _, tt := range tests {
+		t.Run(tt.name, func(t *testing.T) {
+			gotName, gotVer := extractPackageFileInfo(tt.path)
+			if gotName != tt.wantName {
+				t.Errorf("extractPackageFileInfo(%q) name = %q, want %q", tt.path, gotName, tt.wantName)
+			}
+			if gotVer != tt.wantVer {
+				t.Errorf("extractPackageFileInfo(%q) version = %q, want %q", tt.path, gotVer, tt.wantVer)
+			}
+		})
+	}
+}
+
+// TestCacheVersionUniquePerArtifact asserts that distinct PyPI artifacts of
+// the same logical version produce distinct cache keys, and that the bare
+// version returned for logging stays stable.
+func TestCacheVersionUniquePerArtifact(t *testing.T) {
+	// Three wheels of the same version differing only in build/tag, plus a
+	// .zip and a .metadata file for the same version. The cache key uses the
+	// full unique basename, so keys must all differ; the extracted version
+	// must remain the bare stable version for logging/bypass logic.
+	paths := []string{
+		"/foo/foo-1.0.0-cp312-cp312-manylinux.whl",
+		"/foo/foo-1.0.0-cp311-cp311-manylinux.whl",
+		"/foo/foo-1.0.0-py3-none-any.whl",
+		"/foo/foo-1.0.0.zip",
+		"/foo/foo-1.0.0.metadata",
+	}
+
+	seenKeys := make(map[string]bool)
+	for _, path := range paths {
+		_, ver := extractPackageFileInfo(path)
+		if ver != "1.0.0" {
+			t.Errorf("extractPackageFileInfo(%q) version = %q, want stable %q", path, ver, "1.0.0")
+		}
+
+		filename := path
+		if i := strings.LastIndex(filename, "/"); i >= 0 {
+			filename = filename[i+1:]
+		}
+		if seenKeys[filename] {
+			t.Errorf("cache key %q duplicated across artifacts", filename)
+		}
+		seenKeys[filename] = true
+	}
+
+	if len(seenKeys) != len(paths) {
+		t.Errorf("expected %d distinct cache keys, got %d", len(paths), len(seenKeys))
+	}
+}

pkg/scanner/scanner.go

@@ -377,7 +377,7 @@ func (m *Manager) mergeResults(results []*metadata.ScanResult, scannerNames []st
 	// Convert map to slice and count severities
 	for _, vuln := range vulnMap {
 		merged.Vulnerabilities = append(merged.Vulnerabilities, *vuln)
-		severityCounts[strings.ToUpper(vuln.Severity)]++
+		severityCounts[metadata.NormalizeSeverity(vuln.Severity)]++
 	}
 
 	// Update counts
@@ -409,6 +409,21 @@ func (m *Manager) compareSeverity(s1, s2 string) int {
 	return v1 - v2
 }
 
+// normalizeBypassPackageName reduces a stored package cache key to the
+// natural registry/package identifier used in admin bypass targets.
+// Go module packages are stored with a cache key of
+// "modulePath/@v/version.zip" (and .info/.mod variants); the admin-facing
+// target uses the bare module path, e.g. "go/github.com/foo/[email protected]".
+// npm/pypi names are stored unchanged, so this is a no-op for them.
+func normalizeBypassPackageName(registry, name string) string {
+	if registry == "go" {
+		if idx := strings.Index(name, "/@v/"); idx >= 0 {
+			return name[:idx]
+		}
+	}
+	return name
+}
+
 // CheckVulnerabilities checks if a package exceeds vulnerability thresholds
 func (m *Manager) CheckVulnerabilities(ctx context.Context, registry, packageName, version string) (bool, string, error) {
 	if !m.enabled {
@@ -423,8 +438,9 @@ func (m *Manager) CheckVulnerabilities(ctx context.Context, registry, packageNam
 	}
 
 	// Check if entire package is bypassed
-	packageKey := fmt.Sprintf("%s/%s@%s", registry, packageName, version)
-	packageKeyNoVersion := fmt.Sprintf("%s/%s", registry, packageName)
+	bypassName := normalizeBypassPackageName(registry, packageName)
+	packageKey := fmt.Sprintf("%s/%s@%s", registry, bypassName, version)
+	packageKeyNoVersion := fmt.Sprintf("%s/%s", registry, bypassName)
 
 	for _, bypass := range bypasses {
 		if bypass.Type == metadata.BypassTypePackage && bypass.Active {
@@ -499,7 +515,7 @@ func (m *Manager) CheckVulnerabilities(ctx context.Context, registry, packageNam
 				Msg("CVE bypassed by admin")
 			continue
 		}
-		severityCounts[strings.ToUpper(vuln.Severity)]++
+		severityCounts[metadata.NormalizeSeverity(vuln.Severity)]++
 	}
 
 	// Check against thresholds

pkg/scanner/scanner_test.go

@@ -254,3 +254,79 @@ func TestBroadcaster_NilBroadcasterSafe(t *testing.T) {
 	err := mgr.ScanPackage(context.Background(), "npm", "x", "1", "/tmp/dummy")
 	require.NoError(t, err)
 }
+
+// stubBypassStore returns a package bypass and a clean scan result for a
+// Go cache-key package, to exercise FIX-H4 bypass-name normalization.
+type stubBypassStore struct {
+	*stubMetadataStore
+	scan     *metadata.ScanResult
+	bypasses []*metadata.CVEBypass
+}
+
+func (m *stubBypassStore) GetActiveCVEBypasses(context.Context) ([]*metadata.CVEBypass, error) {
+	return m.bypasses, nil
+}
+
+func (m *stubBypassStore) GetScanResult(context.Context, string, string, string) (*metadata.ScanResult, error) {
+	return m.scan, nil
+}
+
+// TestCheckVulnerabilities_GoPackageBypassNaturalTarget verifies a package
+// bypass targeting the natural Go module path matches a package stored under
+// its cache-key name (modulePath/@v/version.zip).
+func TestCheckVulnerabilities_GoPackageBypassNaturalTarget(t *testing.T) {
+	store := &stubBypassStore{
+		stubMetadataStore: &stubMetadataStore{},
+		bypasses: []*metadata.CVEBypass{
+			{
+				ID:     "b1",
+				Type:   metadata.BypassTypePackage,
+				Target: "go/github.com/foo/[email protected]",
+				Active: true,
+			},
+		},
+		scan: &metadata.ScanResult{
+			ID: "r", Scanner: "stub", ScannedAt: time.Now(), Status: metadata.ScanStatusClean,
+		},
+	}
+	mgr := newTestManager(t, store)
+
+	// The package is stored under the cache-key name; the version is passed
+	// separately. The bypass target uses the natural module path.
+	blocked, reason, err := mgr.CheckVulnerabilities(
+		context.Background(), "go", "github.com/foo/bar/@v/v1.2.3.zip", "v1.2.3")
+	require.NoError(t, err)
+	assert.False(t, blocked, "package bypass should unblock the Go package")
+	assert.Equal(t, "", reason)
+}
+
+// TestCheckVulnerabilities_GoPackageBypassNotFound verifies a package bypass
+// targeting a different module does NOT unblock the Go package. Its stored
+// scan result is clean, so CheckVulnerabilities returns not-blocked anyway;
+// to make the package-block path observable we use a scan result with a
+// high-severity vulnerability and zero thresholds (block any non-zero).
+func TestCheckVulnerabilities_GoPackageBypassNotFound(t *testing.T) {
+	store := &stubBypassStore{
+		stubMetadataStore: &stubMetadataStore{},
+		bypasses: []*metadata.CVEBypass{
+			{
+				ID:     "b1",
+				Type:   metadata.BypassTypePackage,
+				Target: "go/github.com/other/[email protected]",
+				Active: true,
+			},
+		},
+		scan: &metadata.ScanResult{
+			ID: "r", Scanner: "stub", ScannedAt: time.Now(), Status: metadata.ScanStatusVulnerable,
+			Vulnerabilities: []metadata.Vulnerability{
+				{ID: "CVE-1", Severity: "HIGH"},
+			},
+		},
+	}
+	mgr := newTestManager(t, store)
+
+	blocked, _, err := mgr.CheckVulnerabilities(
+		context.Background(), "go", "github.com/foo/bar/@v/v1.2.3.zip", "v1.2.3")
+	require.NoError(t, err)
+	assert.True(t, blocked, "a non-matching bypass should not unblock the package")
+}