CVE-2021-4095

medium
Published — · Modified —
CVSS v3
CVSS v2
VIR risk
5.5

Description

A NULL pointer dereference was found in the Linux kernel's KVM when dirty ring logging is enabled without an active vCPU context. An unprivileged local attacker on the host may use this flaw to cause a kernel oops condition and thus a denial of service by issuing a KVM_XEN_HVM_SET_ATTR ioctl. This flaw affects Linux kernel versions prior to 5.17-rc1.

Predictions

Exploit likelihood
20%
Patch ETA

Heuristic predictions, AS-IS, for prioritization only.

Mitigations

vendor Authored 2026-05-27

Vendor advisory: debian — https://security-tracker.debian.org/tracker/CVE-2021-4095

vendor Authored 2026-05-27

Vendor advisory: suse — https://www.suse.com/security/cve/CVE-2021-4095.html

OS impact

OSVersionStatusFixed in
arch archfixed5.15.2-1
suse slesaffected
debian debianbookwormfixed5.17.3-1
debian debianbullseyefixed0
debian debianforkyfixed5.17.3-1
debian debiansidfixed5.17.3-1
debian debiantrixiefixed5.17.3-1

References

Verify integrity in audit chain (admin only). AS-IS.