CVE-2021-26931

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

Description

An issue was discovered in the Linux kernel 2.6.39 through 5.10.16, as used in Xen. Block, net, and SCSI backends consider certain errors a plain bug, deliberately causing a kernel crash. For errors potentially being at least under the influence of guests (such as out of memory conditions), it isn't correct to assume a plain bug. Memory allocations potentially causing such crashes occur only when Linux is running in PV mode, though. This affects drivers/block/xen-blkback/blkback.c and drivers/xen/xen-scsiback.c.

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-2021-26931

vendor Authored 2026-05-27

Vendor advisory: suse — https://www.suse.com/security/cve/CVE-2021-26931.html

OS impact

OSVersionStatusFixed in
arch archfixed5.10.18.hardened1-1
suse slesaffected
debian debianbookwormfixed5.10.19-1
debian debianbullseyefixed5.10.19-1
debian debianforkyfixed5.10.19-1
debian debiansidfixed5.10.19-1
debian debiantrixiefixed5.10.19-1

References

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