Description (CNA)
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.
Affected (CNA)
| Vendor / product | Versions |
|---|---|
| traefik / traefik | affected >= 2.11.9, < 2.11.38; affected >= 3.1.3, < 3.6.9 |
CWE
CWE-178
References
- https://github.com/traefik/traefik/security/advisories/GHSA-92mv-8f8w-wq52
- https://github.com/traefik/traefik/releases/tag/v2.11.38
- https://github.com/traefik/traefik/releases/tag/v3.6.9
ADP enrichment
No English description supplied.
No references supplied.
A flaw was found in Traefik, an HTTP reverse proxy and load balancer. A remote unauthenticated client can exploit a case sensitivity vulnerability in how Traefik processes HTTP/1.1 requests. By using lowercase tokens in the Connection header, an attacker can bypass security protections, leading to the removal of Traefik-managed forwarded identity headers. This could result in information disclosure or misattribution of client requests.