CVE-2021-32813 Information

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.

CVSS Vector

CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:H/A:H

Reference

https://github.com/traefik/traefik/pull/8319/commits/cbaf86a93014a969b8accf39301932c17d0d73f9 https://github.com/traefik/traefik/security/advisories/GHSA-m697-4v8f-55qg https://github.com/traefik/traefik/releases/tag/v2.4.13

Attack Complexity

HIGH

Privileges Required

NONE

User Interaction Required

NONE

Scope

NONE

Confidentiality Impact

UNCHANGED

Integrity Impact

HIGH

Availability Impact

HIGH

Base Score

HIGH

Base Severity

8.1