CVSS 3.1
7.5 highCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:H/A:NCVE-2026-29054
High (7.5) in traefik traefik. EPSS 0.5% chance of exploitation in the next 30 days. Fixed in github.com/traefik/traefik/v2 2.11.38.
Traefik is an HTTP reverse proxy and load balancer. From version 2.11.9 to 2.11.37 and from version 3.1.3 to 3.6.8, there is a potential vulnerability in Traefik managing the Connection header with X-Forwarded headers. When Traefik processes HTTP/1.1 requests, the protection put in place to prevent the removal of Traefik-managed X-Forwarded headers (such as X-Real-Ip, X-Forwarded-Host, X-Forwarded-Port, etc.) via the Connection header does not handle case sensitivity correctly. The Connection tokens are compared case-sensitively against the protected header names, but the actual header deletion operates case-insensitively. As a result, a remote unauthenticated client can use lowercase Connection tokens (e.g. Connection: x-real-ip) to bypass the protection and trigger the removal of Traefik-managed forwarded identity headers. This issue has been patched in versions 2.11.38 and 3.6.9.
Severity
- EPSS
- 0.5% chance of exploitation in the next 30 days; higher than 44% of CVEs (scores of 2026-10-31)
- CWE
- CWE-178
- Published
- Modified
- Record from
- the NVD, synced
Affected
- traefik:traefik
Packages (OSV)
| Advisory | Ecosystem | Package | Affected | Fixed in |
|---|---|---|---|---|
| GHSA-92mv-8f8w-wq52 | Go | github.com/traefik/traefik/v2 | >=2.11.9 <2.11.38 | 2.11.38 |
| GHSA-92mv-8f8w-wq52 | Go | github.com/traefik/traefik/v3 | >=3.1.3 <3.6.9 | 3.6.9 |
| GO-2026-4597 | Go | github.com/traefik/traefik | all versions | no fix published |
| GO-2026-4597 | Go | github.com/traefik/traefik/v2 | >=2.11.9 <2.11.38 | 2.11.38 |
| GO-2026-4597 | Go | github.com/traefik/traefik/v3 | >=3.1.3 <3.6.9 | 3.6.9 |