CVE-2026-26963
MEDIUM6.1EPSS 0.01%Cilium may not enforce host firewall policies when Native Routing, WireGuard and Node Encryption are enabled
Published: 2/19/2026Modified: 2/23/2026
Description
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.
Affected packages (5)
- Bitnami/cilium>= 1.18.0, < 1.18.6
- Bitnami/cilium-operator>= 1.18.0, < 1.18.6
- Bitnami/hubble-relay>= 1.18.0, < 1.18.6
- Go/github.com/cilium/cilium>= 1.18.0, < 1.18.6
- Go/github.com/cilium/cilium>= 1.18.0, < 1.18.6
CVSS scores
| Source | Version | Severity | Vector |
|---|---|---|---|
| osv | CVSS 3.1 | MEDIUM6.1 | CVSS:3.1/AV:A/AC:L/PR:N/UI:N/S:C/C:L/I:L/A:N |
References (6)
- ADVISORYhttps://nvd.nist.gov/vuln/detail/CVE-2026-26963
- PATCHhttps://github.com/cilium/cilium
- WEBhttps://github.com/cilium/cilium/commit/88e28e1e62c0b1a02c3f0fc22d888ac9eefbe885
- WEBhttps://github.com/cilium/cilium/pull/42892
- WEBhttps://github.com/cilium/cilium/releases/tag/v1.18.6
- WEBhttps://github.com/cilium/cilium/security/advisories/GHSA-5r23-prx4-mqg3