Vulnerability · Published Aug 3, 2021 · Assigned by GitHub_M
CVE-2021-32813Drop Headers via Malicious Connection Header
Medium 4.8
In plain English
A medium-severity security flaw in traefik from traefik. There are no confirmed reports of exploitation so far. The chance it is exploited in the next 30 days is estimated at 1.1% (higher than 66% of all known vulnerabilities). Fixed versions are available - upgrade the affected package.
Official 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.
Affected packages & fixed versions
| Ecosystem | Package | Fixed in | Advisory |
|---|---|---|---|
| Go | github.com/traefik/traefik | no fix listed | GHSA-m697-4v8f-55qg |
| Go | github.com/traefik/traefik | no fix listed | GO-2022-0923 |
| Go | github.com/traefik/traefik/v2 | 2.4.13 | GHSA-m697-4v8f-55qg |
| Go | github.com/traefik/traefik/v2 | 2.4.13 | GO-2022-0923 |
Affected products (as reported)
Weakness: CWE-913 · Vector: CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:L/I:L/A:N