GHSA-q6h5-q3q6-f87x

ghsaUSosv

CiliumLocalRedirectPolicy addressMatcher allows cross-namespace service traffic hijacking and can break service translation

view advisory published 2026-07-06Licence: CC-BY-4.0

### Impact Users with the ability to create CiliumLocalRedirectPolicies can specify arbitrary ClusterIPs via addressMatcher, which enables hijacking traffic to Services in any namespace, bypassing the namespace-scoping guarantees enforced by serviceMatcher. In addition, deleting such a policy can corrupt Cilium's internal service state, causing service translation to stop working entirely for the affected Service. ### Patches This issue affects: - Cilium v1.19.0 to v1.19.3 inclusive (fixed in PR #45584) - Cilium v1.18.2 to v1.18.9 inclusive (fixed in PR #45585) - All versions of Cilium prior to v1.17.16 (fixed in PR #45412) This issue has been patched in: - Cilium v1.19.4 - Cilium v1.18.10 - Cilium v1.17.16 ### Workarounds There is no workaround to this issue. ### Acknowledgements The Cilium community has worked together with members of Isovalent to prepare these mitigations. Special thanks to @ysksuzuki for investigating and fixing the issue. ### For more information If there are any questions or comments about this advisory, please reach out on [Slack](https://docs.cilium.io/en/latest/community/community/). To report potential vulnerabilities affecting Cilium, it strongly is encouraged to report them through the security mailing list at [security@cilium.io](mailto:security@cilium.io). This is a private mailing list for the Cilium security team, and reports will be treated as a top priority.

01

describes (1)

Related CVEs.

IDseverity exploitable
CVE-2026-53935US—OT elevated—
Cilium is a networking, observability, and security solution. Prior to 1.17.16, from 1.18.2 to 1.18.9, and from 1.19.0 to 1.19.3, users with the ability to create CiliumLocalRedire…
02

references

External citations — patches, advisories, analysis.

scry

Advisories like this name the exposed products attackers go after on your perimeter. See what is exposed on your perimeter with a free passive scan.

Free scan