CVE-2021-32813

high

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.

References

Details

Source: Mitre, NVD

Published: 2021-08-03

Updated: 2026-06-17

Risk Information

CVSS v2

Base Score: 6.8

Vector: CVSS2#AV:N/AC:M/Au:N/C:P/I:P/A:P

Severity: Medium

CVSS v3

Base Score: 8.1

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

Severity: High

EPSS

EPSS: 0.0042