CVE-2021-28688

Public on 2021-04-20
Modified on 2021-07-15
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.
Severity
Medium
CVSS v3 Base Score
6.5
See breakdown

Affected Packages

Platform Package Release Date Advisory
Amazon Linux 2 kernel 2021-04-20 17:55 ALAS2-2021-1627
Amazon Linux 1 kernel 2021-05-20 21:12 ALAS-2021-1503

CVSS Scores

Score Type Score Vector
Amazon Linux CVSSv2 2.1 AV:L/AC:L/Au:N/C:N/I:N/A:P
Amazon Linux CVSSv3 6.5 CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:C/C:N/I:N/A:H
NVD CVSSv2 2.1 AV:L/AC:L/Au:N/C:N/I:N/A:P
NVD CVSSv3 6.5 CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:C/C:N/I:N/A:H