CVE-2026-56742

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 v3 5.9 MEDIUM

5.9^/10

CVSS v3 : MEDIUM

Vector :

Exploitability : 1.7 / Impact : 3.7

Attack Vector ADJACENT_NETWORK

Attack Complexity LOW

Privileges Required HIGH

User Interaction NONE

Confidentiality Impact LOW

Integrity Impact LOW

Availability Impact LOW

Scope CHANGED

References

Link	Resource
https://github.com/cilium/cilium/commit/7422068aff67ac77c7dcc57aa5b9240c91333deb	Patch
https://github.com/cilium/cilium/commit/e0b1cef513ff910323f3743e9f3e3d86721e4857	Patch
https://github.com/cilium/cilium/commit/f23929cff682d6ed0dc158070812cb302fc0032b	Patch
https://github.com/cilium/cilium/commit/fd47963ea394d5e8fa4a88c40a79063430c512ca	Patch
https://github.com/cilium/cilium/releases/tag/v1.17.17	Release Notes
https://github.com/cilium/cilium/releases/tag/v1.18.11	Release Notes
https://github.com/cilium/cilium/releases/tag/v1.19.5	Release Notes
https://github.com/cilium/cilium/security/advisories/GHSA-w7c2-w76w-5hmj	Vendor Advisory

Configurations

Configuration 1 (hide)

OR	cpe:2.3:a:cilium:cilium::::::::
	cpe:2.3:a:cilium:cilium::::::::
	cpe:2.3:a:cilium:cilium::::::::

History

No history.

Information

Published : 2026-07-15 20:17

Updated : 2026-07-17 17:48

NVD link : CVE-2026-56742

Mitre link : CVE-2026-56742

CVE.ORG link : CVE-2026-56742

JSON object : View

Products Affected

cilium

cilium

CWE

CWE-862

Missing Authorization

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