CVE-2026-26963 MEDIUM

CVE-2026-26963: Cilium may not enforce host firewall policies when Native Routing, WireGuard and Node Encryption are enabled

Vendor Cilium
Product cilium
Weakness CWE-863 · Incorrect authorization
Published February 19, 2026
Last update February 20, 2026
View on NVD All CVEs

CVSS base score

6.1/10
Attack vector Adjacent
Attack complexity Low
Privileges required None
User interaction None
Confidentiality Low
Integrity Low

CVSS vector

CVSS:3.1/AV:A/AC:L/PR:N/UI:N/S:C/C:L/I:L/A:N

What the vulnerability does

01Description

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.

Key dates

02Disclosure timeline

February 19, 2026 CVE published
February 20, 2026 Record updated