CVE-2026-53715
MEDIUMCVE-2026-53715 is a medium-severity (CVSS 5.3) vulnerability in github.com/envoyproxy/gateway. O3 Security confirms whether CVE-2026-53715 is actually reachable in your code before you act, and blocks exploitation at runtime until you patch.
Envoy Gateway: Wasm cache ServeHTTP reads mappingPath2Cache without lock
Real-World Exposure
github.com/envoyproxy/gateway🐹github.com/envoyproxy/gatewayReal-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
Vulnerability report without repro case. Repro case may be added later after harness is complete.
Preconditions (4):
- Pod-network reachability to :18002 (no auth)
- Tenant can create EnvoyExtensionPolicy (baseline)
- Attacker pod floods GET while churning EnvoyExtensionPolicy with distinct Wasm URLs
- Read at :153 must overlap a write at :201/:209 (probabilistic, attacker controls both rates)
Description:
httpserver.go:153 reads s.mappingPath2Cache with no lock while httpserver.go:201/209 write it under s.Lock(); the struct uses a plain map. Writer is tenant-reachable via EnvoyExtensionPolicy translation, reader is pod-network-reachable on :18002 with per-request goroutines. Go's concurrent map read+write detection calls runtime.throw, which net/http's per-conn recover cannot catch, so the controller process exits — cross-tenant control-plane DoS. Capped at MEDIUM: DoS-only, k8s restarts pod, timing-dependent trigger.
Affected Packages
| Ecosystem | Package | Vulnerable range | Fix |
|---|---|---|---|
| 🐹Go | github.com/envoyproxy/gateway | ≥ 1.8.0-rc.0&&< 1.8.1 | 1.8.1 |
| 🐹Go | github.com/envoyproxy/gateway | all versions | 1.7.4 |
Detection & mitigation playbook
Open-source dependencyDetect
Scan your dependency tree (package-lock.json, pnpm-lock.yaml, requirements.txt, go.sum, etc.) for github.com/envoyproxy/gateway. 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.
Fix
Update github.com/envoyproxy/gateway to 1.8.1 or later, then make sure no transitive (indirect) dependency still pins the vulnerable range — O3 confirms CVE-2026-53715 is resolved across your whole dependency graph.
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.
How O3 protects you
O3 pinpoints whether CVE-2026-53715 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 CVE-2026-53715. Runtime protection reduces exposure until a permanent patch is applied and verified — it complements patching, it doesn't replace it.
Frequently Asked Questions
Is CVE-2026-53715 in your dependencies?
O3 detects CVE-2026-53715 across Go dependencies and uses function-level reachability to confirm whether the vulnerable code path is actually reachable — not just present. No false positives.