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GHSA-6vgg-xhvh-38ff

nebula-mesh: POST /api/v1/hosts/{id}/mobile-bundle response lacks Cache-Control: no-store

Also known asGO-2026-5191
Published
Jun 12, 2026
Updated
Jun 25, 2026
Affected
1 pkg
Patched
1 / 1
Exploits
None indexed

Blast Radius

1 pkg affected
🐹github.com/juev/nebula-mesh

Real-time download stats are indexed for npm and PyPI packages. This vulnerability affects Go packages — download data is not available via public APIs for these ecosystems.

Description

internal/api/mobile_bundle.go:62-66 sets only Content-Type: application/yaml. The Web-UI sibling at internal/web/handlers.go:1316-1321 sets Cache-Control: no-store, Pragma: no-cache, Expires: 0, X-Content-Type-Options: nosniff — and has a test asserting it. The API path was missed.

Affected

All released versions up to v0.3.0.

Threat model

The endpoint returns a freshly minted X25519 private key inline. Without no-store, any intermediary proxy or CDN that caches 200 OK YAML responses retains the private key for its cache TTL. Same applies to browser disk cache for direct API hits. Combined with the cross-tenant authz advisory (critical), even a corrected authz layer would still leak via cache after fix.

Suggested fix

Copy the four headers from the Web sibling:

w.Header().Set("Content-Type", "application/yaml; charset=utf-8")
w.Header().Set("Cache-Control", "no-store")
w.Header().Set("Pragma", "no-cache")
w.Header().Set("Expires", "0")
w.Header().Set("X-Content-Type-Options", "nosniff")

Mirrors internal/web/handlers.go:1316-1321. Add a parallel test to the existing web-side coverage.

Suggested patch

Verified locally: go vet, go test -race -count=1 ./..., golangci-lint v2.12 all clean.

diff --git a/internal/api/mobile_bundle.go b/internal/api/mobile_bundle.go
index fc09da0..73152eb 100644
--- a/internal/api/mobile_bundle.go
+++ b/internal/api/mobile_bundle.go
@@ -58,8 +58,15 @@ func (s *Server) handleMobileBundle(w http.ResponseWriter, r *http.Request) {
 		return
 	}
 
-	// Return YAML bundle with proper content-type
+	// Return YAML bundle with proper content-type. The bundle inlines a
+	// freshly-minted X25519 private key, so suppress every layer of cache
+	// between server and operator (intermediate proxies/CDNs, browser disk
+	// cache). Mirrors the Web-UI sibling at internal/web/handlers.go.
 	w.Header().Set("Content-Type", "application/yaml; charset=utf-8")
+	w.Header().Set("Cache-Control", "no-store")
+	w.Header().Set("Pragma", "no-cache")
+	w.Header().Set("Expires", "0")
+	w.Header().Set("X-Content-Type-Options", "nosniff")
 	w.WriteHeader(http.StatusOK)
 	if _, err := w.Write(bundle); err != nil {
 		s.logger.Error("write mobile bundle response", "error", err)
diff --git a/internal/api/mobile_bundle_test.go b/internal/api/mobile_bundle_test.go
index dcb8cd9..da08b01 100644
--- a/internal/api/mobile_bundle_test.go
+++ b/internal/api/mobile_bundle_test.go
@@ -52,6 +52,19 @@ func TestHandleMobileBundle_Success(t *testing.T) {
 		t.Errorf("Content-Type = %q, want 'application/yaml; charset=utf-8'", ct)
 	}
 
+	// Bundle inlines a private key — every cache between server and operator
+	// must drop the response. Mirrors the Web-UI sibling's headers.
+	for header, want := range map[string]string{
+		"Cache-Control":         "no-store",
+		"Pragma":                "no-cache",
+		"Expires":               "0",
+		"X-Content-Type-Options": "nosniff",
+	} {
+		if got := w.Header().Get(header); got != want {
+			t.Errorf("%s = %q, want %q", header, got, want)
+		}
+	}
+
 	// Verify body is valid YAML with expected keys
 	var yamlData map[string]interface{}
 	if err := yaml.Unmarshal(w.Body.Bytes(), &yamlData); err != nil {

Affected Packages

1 total 1 fixed
EcosystemPackageVulnerable rangeFix
🐹Gogithub.com/juev/nebula-meshall versions0.3.2

Detection & mitigation playbook

Open-source dependency
  1. Detect

    Scan your dependency tree (package-lock.json, pnpm-lock.yaml, requirements.txt, go.sum, etc.) for github.com/juev/nebula-mesh. O3's reachability analysis confirms whether the vulnerable code path is actually invoked in your application, so you act on real exposure instead of every transitive match.

  2. Fix

    Update github.com/juev/nebula-mesh to 0.3.2 or later, then make sure no transitive (indirect) dependency still pins the vulnerable range — O3 confirms GHSA-6vgg-xhvh-38ff is resolved across your whole dependency graph.

  3. Workarounds

    If you can't upgrade right away: gate or disable the affected feature, validate untrusted input at the boundary, and avoid passing attacker-controlled data into the vulnerable path. O3's runtime protection blocks exploitation in production as an interim safeguard until the upgrade lands.

  4. How O3 protects you

    O3 pinpoints whether GHSA-6vgg-xhvh-38ff is reachable in your code and exactly where to fix it, then blocks exploitation in production at runtime until the patched version is deployed.

Tailored to GHSA-6vgg-xhvh-38ff. Runtime protection reduces exposure until a permanent patch is applied and verified — it complements patching, it doesn't replace it.

Frequently Asked Questions

`internal/api/mobile_bundle.go:62-66` sets only `Content-Type: application/yaml`. The Web-UI sibling at `internal/web/handlers.go:1316-1321` sets `Cache-Control: no-store`, `Pragma: no-cache`, `Expires: 0`, `X-Content-Type-Options: nosniff` — and has a test asserting it. The API path was missed. ## Affected All released versions up to v0.3.0. ## Threat model The endpoint returns a freshly minted X25519 private key inline. Without `no-store`, any intermediary proxy or CDN that caches `200 OK` YAML responses retains the private key for its cache TTL. Same applies to browser disk cache for dire
O3 Security · Impact-Aware SCA

Is GHSA-6vgg-xhvh-38ff in your dependencies?

O3 detects GHSA-6vgg-xhvh-38ff across Go dependencies and uses function-level reachability to confirm whether the vulnerable code path is actually reachable — not just present. No false positives.