Medium 5.9Published Jul 15, 2026

CVE-2026-56742Cilium: Namespaced HTTPRoutes can redirect traffic to other namespaces

Updated under an hour ago (Oct 28, 2026, 1:23 AM ET)

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Every CVE for cilium

Exploited in the last 30 days

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: 5.9 MEDIUM (v3.1, CNA)CVSS:3.1/AV:A/AC:L/PR:H/UI:N/S:C/C:L/I:L/A:L
Weakness (CWE): CWE-862
Known exploited: Not in CISA's KEV catalog
EPSS (exploitation in the next 30 days): Not loaded for this CVE
Assigned by: GitHub_M
NVD analysis: Analyzed
Record last updated: Jul 16, 2026
First seen by InfoSec Signals: Oct 9, 2026

Affected products

Affected products

cilium cilium cilium:cilium (from the name)	before 1.17.17; from 1.18.0, < 1.18.11; from 1.19.0, < 1.19.5	CNA record
cilium cilium cilium:cilium	before 1.17.17; from 1.18.0 before 1.18.11; from 1.19.0 before 1.19.5	NVD

References

References

https://github.com/cilium/cilium/security/advisories/GHSA-w7c2-w76w-5hmj	x-refsource-confirm, vendor-advisory
https://github.com/cilium/cilium/commit/7422068aff67ac77c7dcc57aa5b9240c91333deb	x-refsource-misc, patch
https://github.com/cilium/cilium/commit/e0b1cef513ff910323f3743e9f3e3d86721e4857	x-refsource-misc, patch
https://github.com/cilium/cilium/commit/f23929cff682d6ed0dc158070812cb302fc0032b	x-refsource-misc, patch
https://github.com/cilium/cilium/commit/fd47963ea394d5e8fa4a88c40a79063430c512ca	x-refsource-misc, patch
https://github.com/cilium/cilium/releases/tag/v1.17.17	x-refsource-misc, release-notes
https://github.com/cilium/cilium/releases/tag/v1.18.11	x-refsource-misc, release-notes
https://github.com/cilium/cilium/releases/tag/v1.19.5	x-refsource-misc, release-notes

The CVE record on cve.org NVD's entry

The CVE record is authoritative. Products marked “from the name” were identified from the CNA's free-text names, not a CPE, and are matched less certainly. This product uses the NVD API but is not endorsed or certified by the NVD.