CVE-2021-32813

Drop Headers via Malicious Connection Header

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.

Category

4.8
CVSS
Severity: Medium
CVSS 3.1 •
CVSS 2.0 •
EPSS 0.38%
Third-Party Advisory github.com Third-Party Advisory github.com Third-Party Advisory github.com
Affected: traefik traefik
Published at:
Updated at:

References

Frequently Asked Questions

What is the severity of CVE-2021-32813?
CVE-2021-32813 has been scored as a medium severity vulnerability.
How to fix CVE-2021-32813?
To fix CVE-2021-32813, make sure you are using an up-to-date version of the affected component(s) by checking the vendor release notes. As for now, there are no other specific guidelines available.
Is CVE-2021-32813 being actively exploited in the wild?
As for now, there are no information to confirm that CVE-2021-32813 is being actively exploited. According to its EPSS score, there is a ~0% probability that this vulnerability will be exploited by malicious actors in the next 30 days.
What software or system is affected by CVE-2021-32813?
CVE-2021-32813 affects traefik traefik.
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