CVE-2021-28688

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

Description

The fix for XSA-365 includes initialization of pointers such that subsequent cleanup code wouldn't use uninitialized or stale values. This initialization went too far and may under certain conditions also overwrite pointers which are in need of cleaning up. The lack of cleanup would result in leaking persistent grants. The leak in turn would prevent fully cleaning up after a respective guest has died, leaving around zombie domains. All Linux versions having the fix for XSA-365 applied are vulnerable. XSA-365 was classified to affect versions back to at least 3.11.

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-2021-28688

vendor Authored 2026-05-27

Vendor advisory: suse — https://www.suse.com/security/cve/CVE-2021-28688.html

OS impact

OSVersionStatusFixed in
arch archfixed5.10.27-1
suse slesaffected
debian debianbookwormfixed5.10.28-1
debian debianbullseyefixed5.10.28-1
debian debianforkyfixed5.10.28-1
debian debiansidfixed5.10.28-1
debian debiantrixiefixed5.10.28-1

References

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