CVE-2026-41520 Cillium exposes sensitive information included in the cilium-bugtool debug archive
Attackers can obtain sensitive data from Cilium bugtool archives when WireGuard encryption is enabled, requiring an upgrade to patched versions.
- Exploited in the wild
- Not known
- Login needed
- An administrator
- Attackable
- Local or same network only
- Victim action needed
- Not needed
- Fix
- Available
What is CVE-2026-41520?
CVE-2026-41520 is a high-severity vulnerability in cilium, published on 8 May 2026. It can only be exploited from the same machine or local network, with no action from the victim.
Official description
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.
Which versions are affected by CVE-2026-41520?
10 open source packages ship an affected version, including github.com/cilium/cilium, cilium and cilium-operator. It affects 1 product.
| Package | Affected | Fixed in |
|---|---|---|
github.com/cilium/cilium Go | All versions | 1.17.15, 1.18.9, 1.19.3 |
github.com/cilium/cilium Go | All versions | 1.17.15 |
github.com/cilium/cilium Go | All versions | 1.17.15 |
github.com/cilium/cilium Go | From 1.18.0 | 1.18.9 |
github.com/cilium/cilium Go | From 1.18.0 | 1.18.9 |
github.com/cilium/cilium Go | From 1.19.0 | 1.19.3 |
4 more packages
github.com/cilium/cilium Go | From 1.19.0 | 1.19.3 |
cilium Bitnami | All versions | 1.17.15, 1.18.9, 1.19.3 |
cilium-operator Bitnami | All versions | 1.17.15, 1.18.9, 1.19.3 |
hubble-relay Bitnami | All versions | 1.17.15, 1.18.9, 1.19.3 |
Products include Cilium Cilium.
How do I fix CVE-2026-41520?
Upgrade github.com/cilium/cilium to a fixed version for your release line: 1.17.15, 1.18.9 or 1.19.3.
Is CVE-2026-41520 being exploited?
There is no known exploitation of CVE-2026-41520 in the wild and no public exploit code.
Other vulnerabilities in cilium
- CVE-2026-49445 Cilium: Sensitive information disclosure and cluster disruption via local Envoy admin socket access
- CVE-2022-29178 Incorrect Default Permissions in Cilium
- CVE-2024-28860 Insecure IPsec transport encryption in Cilium
- CVE-2024-37307 Cilium leaks sensitive information in cilium-bugtool
- CVE-2023-39347 Cilium NetworkPolicy bypass via pod labels
Sources
Also known as BIT-cilium-2026-41520, BIT-cilium-operator-2026-41520, BIT-hubble-relay-2026-41520, GHSA-gj49-89wh-h4gj, GO-2026-5400, MINI-2982-g347-rjq7 and 17 more.