CVE-2026-26963

Cilium is a networking, observability, and security solution with an eBPF-based dataplane. Versions 1.18.0 through 1.18.5 will incorrectly permit traffic from Pods on other nodes when Native Routing, WireGuard and Node Encryption are enabled. This issue has been fixed in version 1.18.6.

CVSS v3 6.1 MEDIUM

6.1^/10

CVSS v3 : MEDIUM

Vector :

Exploitability : 2.8 / Impact : 2.7

Attack Vector ADJACENT_NETWORK

Attack Complexity LOW

Privileges Required NONE

User Interaction NONE

Confidentiality Impact LOW

Integrity Impact LOW

Availability Impact NONE

Scope CHANGED

References

Link	Resource
https://github.com/cilium/cilium/commit/88e28e1e62c0b1a02c3f0fc22d888ac9eefbe885	Patch
https://github.com/cilium/cilium/pull/42892	Issue Tracking
https://github.com/cilium/cilium/releases/tag/v1.18.6	Release Notes
https://github.com/cilium/cilium/security/advisories/GHSA-5r23-prx4-mqg3	Patch Vendor Advisory

Configurations

Configuration 1 (hide)

cpe:2.3:a:cilium:cilium:*:*:*:*:*:*:*:*

History

20 Feb 2026, 20:12

Type	Values Removed	Values Added
First Time		Cilium Cilium cilium
References	~~() https://github.com/cilium/cilium/commit/88e28e1e62c0b1a02c3f0fc22d888ac9eefbe885 -~~	() https://github.com/cilium/cilium/commit/88e28e1e62c0b1a02c3f0fc22d888ac9eefbe885 - Patch
References	~~() https://github.com/cilium/cilium/pull/42892 -~~	() https://github.com/cilium/cilium/pull/42892 - Issue Tracking
References	~~() https://github.com/cilium/cilium/releases/tag/v1.18.6 -~~	() https://github.com/cilium/cilium/releases/tag/v1.18.6 - Release Notes
References	~~() https://github.com/cilium/cilium/security/advisories/GHSA-5r23-prx4-mqg3 -~~	() https://github.com/cilium/cilium/security/advisories/GHSA-5r23-prx4-mqg3 - Patch, Vendor Advisory
CPE		cpe:2.3:a:cilium:cilium::::::::

20 Feb 2026, 00:16

Type	Values Removed	Values Added
New CVE

Information

Published : 2026-02-20 00:16

Updated : 2026-02-20 20:12

NVD link : CVE-2026-26963

Mitre link : CVE-2026-26963

CVE.ORG link : CVE-2026-26963

JSON object : View

Products Affected

cilium

cilium

CWE

CWE-863

Incorrect Authorization

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