CVE-2021-31999

Rancher: Privilege escalation vulnerability via malicious Connection header

Description

A Reliance on Untrusted Inputs in a Security Decision vulnerability in Rancher allows users in the cluster to act as others users in the cluster by forging the "Impersonate-User" or "Impersonate-Group" headers. This issue affects: Rancher versions prior to 2.5.9. Rancher versions prior to 2.4.16.

Category

8.8
CVSS
Severity: High
CVSS 3.1 •
CVSS 2.0 •
EPSS 0.35%
Third-Party Advisory suse.com
Affected: Rancher Rancher
Affected: Rancher SUSE Linux Enterprise Server 15
Published at:
Updated at:

References

Link Tags
https://bugzilla.suse.com/show_bug.cgi?id=1187084 third party advisory release notes issue tracking

Frequently Asked Questions

What is the severity of CVE-2021-31999?
CVE-2021-31999 has been scored as a high severity vulnerability.
How to fix CVE-2021-31999?
To fix CVE-2021-31999, 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-2021-31999 being actively exploited in the wild?
As for now, there are no information to confirm that CVE-2021-31999 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-2021-31999?
CVE-2021-31999 affects Rancher Rancher, Rancher SUSE Linux Enterprise Server 15.
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