Description
Traefik is an HTTP reverse proxy and load balancer. Prior to version 2.4.13, there exists a potential header vulnerability in Traefik's handling of the Connection header. Active exploitation of this issue is unlikely, as it requires that a removed header would lead to a privilege escalation, however, the Traefik team has addressed this issue to prevent any potential abuse. If one has a chain of Traefik middlewares, and one of them sets a request header, then sending a request with a certain Connection header will cause it to be removed before the request is sent. In this case, the backend does not see the request header. A patch is available in version 2.4.13. There are no known workarounds aside from upgrading.
Analysis and contextual insights are available on OpenCVE Cloud.
Remediation
No vendor fix or workaround currently provided.
Additional remediation guidance may be available on OpenCVE Cloud.
Tracking
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Advisories
| Source | ID | Title |
|---|---|---|
EUVD |
EUVD-2021-1790 | Traefik is an HTTP reverse proxy and load balancer. Prior to version 2.4.13, there exists a potential header vulnerability in Traefik's handling of the Connection header. Active exploitation of this issue is unlikely, as it requires that a removed header would lead to a privilege escalation, however, the Traefik team has addressed this issue to prevent any potential abuse. If one has a chain of Traefik middlewares, and one of them sets a request header, then sending a request with a certain Connection header will cause it to be removed before the request is sent. In this case, the backend does not see the request header. A patch is available in version 2.4.13. There are no known workarounds aside from upgrading. |
Github GHSA |
GHSA-m697-4v8f-55qg | Header dropping in traefik |
References
History
Tue, 24 Feb 2026 17:00:00 +0000
| Type | Values Removed | Values Added |
|---|---|---|
| Title | Drop Headers via Malicious Connection Header | Drop Headers via Malicious Connection Header |
Status: PUBLISHED
Assigner: GitHub_M
Published:
Updated: 2024-08-03T23:33:55.883Z
Reserved: 2021-05-12T00:00:00.000Z
Link: CVE-2021-32813
No data.
Status : Modified
Published: 2021-08-03T23:15:07.370
Modified: 2024-11-21T06:07:48.107
Link: CVE-2021-32813
No data.
OpenCVE Enrichment
No data.
Weaknesses
EUVD
Github GHSA