Vulnerability Description
Cilium is a networking, observability, and security solution. Prior to 1.17.17, 1.18.11, and 1.19.5, Cilium clusters using Gateway API allow users with permissions to create or update namespaced HTTPRoutes to mirror HTTP traffic to any Service in any namespace, bypassing the ReferenceGrant authorization mechanism. Gateway API functionality is disabled by default. This issue is fixed in versions 1.17.17, 1.18.11, and 1.19.5.
CVSS Score
MEDIUM
Affected Products
| Vendor | Product | Versions |
|---|---|---|
| Cilium | Cilium | < 1.17.17 |
Related Weaknesses (CWE)
References
- https://github.com/cilium/cilium/commit/7422068aff67ac77c7dcc57aa5b9240c91333debPatch
- https://github.com/cilium/cilium/commit/e0b1cef513ff910323f3743e9f3e3d86721e4857Patch
- https://github.com/cilium/cilium/commit/f23929cff682d6ed0dc158070812cb302fc0032bPatch
- https://github.com/cilium/cilium/commit/fd47963ea394d5e8fa4a88c40a79063430c512caPatch
- https://github.com/cilium/cilium/releases/tag/v1.17.17Release Notes
- https://github.com/cilium/cilium/releases/tag/v1.18.11Release Notes
- https://github.com/cilium/cilium/releases/tag/v1.19.5Release Notes
- https://github.com/cilium/cilium/security/advisories/GHSA-w7c2-w76w-5hmjVendor Advisory
FAQ
What is CVE-2026-56742?
CVE-2026-56742 is a vulnerability with a CVSS score of 5.9 (MEDIUM). Cilium is a networking, observability, and security solution. Prior to 1.17.17, 1.18.11, and 1.19.5, Cilium clusters using Gateway API allow users with permissions to create or update namespaced HTTPR...
How severe is CVE-2026-56742?
CVE-2026-56742 has been rated MEDIUM with a CVSS base score of 5.9/10. Review the CVSS metrics above for detailed severity breakdown.
Is there a patch for CVE-2026-56742?
Check the references section above for vendor advisories and patch information. Affected products include: Cilium Cilium.