Information disclosure in Cilium
CVE-2026-41520
Cilium is a networking, observability, and security solution with an eBPF-based dataplane. Prior to versions 1.17.15, 1.18.9, and 1.19.3, the output of cilium-bugtool can contain sensitive data when the tool is run against Cilium deployments with WireGuard encryption enabled. This issue has been patched in versions 1.17.15, 1.18.9, and 1.19.3.
Vulnerability class: Information Disclosure
Published · last modified .
CVSS v3 metric
CVSS v3 base score 7.9 (High). Vector: CVSS:3.1/AV:L/AC:L/PR:H/UI:N/S:C/C:H/I:H/A:N.
EPSS exploit prediction
EPSS: 0.001 (0.2th percentile), scored .
Very low probability of exploitation in the next 30 days; routine patching cadence is appropriate. 0th percentile — 0.2% of CVEs in the catalogue have a lower EPSS than this one. How to read EPSS.
EPSS over last 30 days · oldest: 0.001 · newest: 0.001 · change: +0.000
Affected products
- Cilium — versions < 1.17.15, >= 1.18.0, < 1.18.9, >= 1.19.0, < 1.19.3
Weakness classification (CWE)
References
- github.com/cilium/cilium/security/advisories/GHSA-gj49-89wh-h4gj (Mitigation, Vendor Advisory)
- github.com/cilium/cilium/releases/tag/v1.17.15 (Product, Release Notes)
- github.com/cilium/cilium/releases/tag/v1.18.9 (Product, Release Notes)
- github.com/cilium/cilium/releases/tag/v1.19.3 (Product, Release Notes)
Frequently asked questions
- What is CVE-2026-41520?
- CVE-2026-41520 is a high-severity vulnerability in Cilium, classified under Information Disclosure. CVSS score: 7.9/10. Published 2026-05-08.
- How severe is CVE-2026-41520?
- High severity. CVSS v3 base score is 7.9 out of 10.