CVE-2021-3631

Public Exploit

Description

A flaw was found in libvirt while it generates SELinux MCS category pairs for VMs' dynamic labels. This flaw allows one exploited guest to access files labeled for another guest, resulting in the breaking out of sVirt confinement. The highest threat from this vulnerability is to confidentiality and integrity.

Category

6.3
CVSS
Severity: Medium
CVSS 3.1 •
CVSS 2.0 •
EPSS 0.04%
Vendor Advisory gentoo.org Vendor Advisory redhat.com Vendor Advisory redhat.com
Affected: n/a libvirt
Published at:
Updated at:

References

Link Tags
https://bugzilla.redhat.com/show_bug.cgi?id=1977726 vendor advisory issue tracking
https://gitlab.com/libvirt/libvirt/-/issues/153 third party advisory exploit
https://gitlab.com/libvirt/libvirt/-/commit/15073504dbb624d3f6c911e85557019d3620fdb2 third party advisory patch
https://access.redhat.com/errata/RHSA-2021:3631 vendor advisory
https://security.netapp.com/advisory/ntap-20220331-0010/ third party advisory
https://security.gentoo.org/glsa/202210-06 third party advisory vendor advisory
https://lists.debian.org/debian-lts-announce/2024/04/msg00000.html mailing list

Frequently Asked Questions

What is the severity of CVE-2021-3631?
CVE-2021-3631 has been scored as a medium severity vulnerability.
How to fix CVE-2021-3631?
To fix CVE-2021-3631, 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-2021-3631 being actively exploited in the wild?
It is possible that CVE-2021-3631 is being exploited or will be exploited in a near future based on public information. 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-2021-3631?
CVE-2021-3631 affects n/a libvirt.
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