Medium 6.1Published Feb 19, 2026

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

Updated under an hour ago (Oct 28, 2026, 11:10 AM ET)

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No exploitation reported and no EPSS estimate yet.

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Every CVE for cilium

Exploited in the last 30 days

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: 6.1 MEDIUM (v3.1, CNA)CVSS:3.1/AV:A/AC:L/PR:N/UI:N/S:C/C:L/I:L/A:N
Weakness (CWE): CWE-863
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: Feb 20, 2026
First seen by InfoSec Signals: Oct 9, 2026

Affected products

Affected products

cilium cilium cilium:cilium (from the name)	from 1.18.0, < 1.18.6	CNA record
cilium cilium cilium:cilium	from 1.18.0 before 1.18.6	NVD

References

References

https://github.com/cilium/cilium/security/advisories/GHSA-5r23-prx4-mqg3	x-refsource-confirm, patch, vendor-advisory
https://github.com/cilium/cilium/pull/42892	x-refsource-misc, issue-tracking
https://github.com/cilium/cilium/commit/88e28e1e62c0b1a02c3f0fc22d888ac9eefbe885	x-refsource-misc, patch
https://github.com/cilium/cilium/releases/tag/v1.18.6	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.