Upstream information
Description
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.SUSE information
Overall state of this security issue: Resolved
This issue is currently rated as having important severity.
| CVSS detail | CNA (GitHub) |
|---|---|
| Base Score | 7.5 |
| Vector | CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:H/A:N |
| Attack Vector | Network |
| Attack Complexity | Low |
| Privileges Required | None |
| User Interaction | None |
| Scope | Unchanged |
| Confidentiality Impact | None |
| Integrity Impact | High |
| Availability Impact | None |
| CVSSv3 Version | 3.1 |
SUSE Security Advisories:
- SUSE-SU-2026:1042-1, published 2026-03-25T15:06:58Z
List of released packages
| Product(s) | Fixed package version(s) | References |
|---|---|---|
| openSUSE Tumbleweed |
| Patchnames: openSUSE-Tumbleweed-2026-10314 openSUSE-Tumbleweed-2026-10323 |
Status of this issue by product and package
Please note that this evaluation state might be work in progress, incomplete or outdated. Also information for service packs in the LTSS phase is only included for issues meeting the LTSS criteria. If in doubt, feel free to contact us for clarification. The updates are grouped by state of their lifecycle. SUSE product lifecycles are documented on the lifecycle page.
| Product(s) | Source package | State |
|---|---|---|
| Products under general support and receiving all security fixes. | ||
| openSUSE Leap 15.6 | govulncheck-vulndb | Released |
| Products past their end of life and not receiving proactive updates anymore. | ||
| SUSE Linux Enterprise Module for Package Hub 15 SP5 | govulncheck-vulndb | Affected |
| SUSE Linux Enterprise Module for Package Hub 15 SP6 | govulncheck-vulndb | Affected |
| openSUSE Leap 15.5 | govulncheck-vulndb | Affected |
SUSE Timeline for this CVE
CVE page created: Thu Mar 5 22:04:29 2026CVE page last modified: Thu Mar 26 20:49:59 2026