Cilium eBPF filters may be temporarily removed during agent restartGHSA-r5x6-w42p-jhpp
MEDIUMFix: cilium/cilium#24336GHSA-r5x6-w42p-jhpp is a medium-severity (CVSS 6.5) CWE-755 vulnerability in github.com/cilium/cilium. A fix is available for github.com/cilium/cilium — see the affected versions and patch details below.
Exploitation Status
No confirmed exploitation observed yet
- CISA’s own triage has not observed active exploitation or public proof-of-concept code for this CVE as of its last assessment.
Exploitation and automatability from CISA’s SSVC triage for GHSA-r5x6-w42p-jhpp.
EPSS Exploitation Probability
Probability of exploitation in the next 30 days, from FIRST.org EPSS.
How urgent is this, really
Where this sits among everything scored
Real-World Exposure
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
When Cilium is started, there is a short period when Cilium eBPF programs are not attached to the host. During this period, the host does not implement any of Cilium's featureset. This can cause disruption to newly established connections during this period due to the lack of Load Balancing, or can cause Network Policy bypass due to the lack of Network Policy enforcement during the window. This vulnerability impacts any Cilium-managed endpoints on the node (such as Kubernetes Pods), as well as the host network namespace (including Host Firewall).
Patches
This vulnerability is fixed by https://github.com/cilium/cilium/pull/24336, included in Cilium 1.13.1 or later. Cilium releases 1.12.x, 1.11.x and earlier are not affected.
Workarounds
There are no known workarounds.
Acknowledgements
The Cilium community has worked together with members of Isovalent to prepare these mitigations. Special thanks to Louis DeLosSantos and Timo Beckers for investigating and fixing the issue.
For more information
If you have any questions or comments about this advisory, please reach out on Slack.
As usual, if you think you found a related vulnerability, we strongly encourage you to report security vulnerabilities to our private security mailing list: [email protected] - first, before disclosing them in any public forums. This is a private mailing list where only members of the Cilium internal security team are subscribed to, and is treated as top priority.
Affected Packages
| Ecosystem | Package | Vulnerable range | Fix |
|---|---|---|---|
| 🐹Go | github.com/cilium/cilium | ≥ 1.13.0&&< 1.13.1 | 1.13.1go get github.com/cilium/cilium@v1.13.1 |
Affected Products
ciliumciliumDetection & 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, including transitive dependencies — a direct dependency you never call can still pull in a vulnerable version.
Fix
Update github.com/cilium/cilium to 1.13.1 or later, then make sure no transitive (indirect) dependency still pins the vulnerable range — O3 confirms GHSA-r5x6-w42p-jhpp 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.
Frequently Asked Questions
Is GHSA-r5x6-w42p-jhpp in your dependencies?
Find it across Go, including transitive dependencies.