CVE-2021-28688

MediumCVSS 6.5/10Last modified Jun 17, 2026

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.

Metrics

CVSS 3.1 6.5/10CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:C/C:N/I:N/A:H

Weakness enumeration

Affected software

No affected versions have been published.

Timeline

Published
Apr 6, 2021
Last modified
Jun 17, 2026
NVD status
Modified

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CVE-2021-28688: Medium severity, CVSS 6.5 | Vulnix