GHSA-hxv8-4j4r-cqgv
MEDIUMCilium L7 proxy may bypass Kubernetes NetworkPolicy for same-node traffic
EPSS Exploitation Probability
EPSS (Exploit Prediction Scoring System) is a daily probability model maintained by FIRST.org. It estimates the likelihood a CVE will be exploited in production environments within the next 30 days, derived from real-world threat intelligence signals.
Blast Radius
github.com/cilium/cilium🐹github.com/cilium/cilium🐹github.com/cilium/ciliumReal-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
Impact
Ingress Network Policies are not enforced for traffic from pods to L7 Services (Envoy, GAMMA) with a local backend on the same node, when Per-Endpoint Routing is enabled and BPF Host Routing is disabled.
Per-Endpoint Routing is disabled by default, but is automatically enabled in deployments using cloud IPAM, including Cilium ENI on EKS (eni.enabled), AlibabaCloud ENI (alibabacloud.enabled), Azure IPAM (azure.enabled, but not AKS BYOCNI), and some GKE deployments (gke.enabled; managed offerings such as GKE Dataplane V2 may use different defaults). It is typically not enabled in tunneled deployments, and chaining deployments are not affected. In practice, Amazon EKS with Cilium ENI mode is likely the most common affected environment.
Patches
This issue was fixed by #44693.
This issue affects:
- Cilium v1.19 between v1.19.0 and v1.19.1 inclusive
- Cilium v1.18 between v1.18.0 and v1.18.7 inclusive
- All versions of Cilium prior to v1.17.13
This issue is fixed in:
- Cilium v1.19.2
- Cilium v1.18.8
- Cilium v1.17.14
Workarounds
Disclaimer: There is currently no officially verified or comprehensive workaround for this issue. The only option would be to disable per-endpoint routes, but this will likely cause disruptions to ongoing connections, and potential conflicts if running in cloud providers.
Acknowledgements
The Cilium community has worked together with members of the Northflank and Isovalent teams to prepare these mitigations. Cilium thanks @sudeephb and @Champ-Goblem for reporting the issue and to @smagnani96 and @julianwiedmann for helping with the resolution.
For more information
Anyone who believes a vulnerability affecting Cilium has been found is strongly encouraged to report it to the security mailing list at [email protected]. This is a private mailing list for the Cilium security team, and any such report will be treated as top priority. Please also address any comments or questions on this advisory to the same mailing list.
Affected Packages
| Ecosystem | Package | Vulnerable range | Fix |
|---|---|---|---|
| 🐹Go | github.com/cilium/cilium | all versions | 1.17.14 |
| 🐹Go | github.com/cilium/cilium | ≥ 1.18.0&&< 1.18.8 | 1.18.8 |
| 🐹Go | github.com/cilium/cilium | ≥ 1.19.0&&< 1.19.2 | 1.19.2 |
Detection & mitigation playbook
Open-source dependencyDetect
Scan your dependency tree (package-lock.json, pnpm-lock.yaml, requirements.txt, go.sum, etc.) for github.com/cilium/cilium. 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/cilium/cilium to 1.17.14 or later, then make sure no transitive (indirect) dependency still pins the vulnerable range — O3 confirms GHSA-hxv8-4j4r-cqgv 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 GHSA-hxv8-4j4r-cqgv 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-hxv8-4j4r-cqgv. Runtime protection reduces exposure until a permanent patch is applied and verified — it complements patching, it doesn't replace it.
Frequently Asked Questions
Is GHSA-hxv8-4j4r-cqgv in your dependencies?
O3 detects GHSA-hxv8-4j4r-cqgv across Go dependencies and uses function-level reachability to confirm whether the vulnerable code path is actually reachable — not just present. No false positives.