This update for the Linux Kernel 4.4.180-94_153 fixes several issues. The following security issues were fixed: - CVE-2021-0920: Fixed a local privilege escalation due to an use after free bug in unix_gc . - CVE-2021-28688: Fixed XSA-365 that 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 .