CVE-2021-3975

Name	CVE-2021-3975
Description	A use-after-free flaw was found in libvirt. The qemuMonitorUnregister() function in qemuProcessHandleMonitorEOF is called using multiple threads without being adequately protected by a monitor lock. This flaw could be triggered by the virConnectGetAllDomainStats API when the guest is shutting down. An unprivileged client with a read-only connection could use this flaw to perform a denial of service attack by causing the libvirt daemon to crash.
Source	CVE (at NVD; CERT, LWN, oss-sec, fulldisc, bugtraq, EDB, Metasploit, Red Hat, Ubuntu, Gentoo, SUSE bugzilla/CVE, Mageia, GitHub advisories/code/issues, web search, more)

Vulnerable and fixed packages

The table below lists information on source packages.

Source Package	Release	Version	Status
libvirt (PTS)	buster	5.0.0-4+deb10u1	vulnerable
	bullseye	7.0.0-3	vulnerable
	bookworm, sid	9.0.0-2	fixed

The information below is based on the following data on fixed versions.

Package	Type	Release	Fixed Version	Urgency	Origin	Debian Bugs
libvirt	source	(unstable)	7.6.0-1

Notes

[bullseye] - libvirt <no-dsa> (Minor issue)
[buster] - libvirt <no-dsa> (Minor issue)
[stretch] - libvirt <no-dsa> (Minor issue)
https://bugzilla.redhat.com/show_bug.cgi?id=2024326
Fixed by: https://github.com/libvirt/libvirt/commit/1ac703a7d0789e46833f4013a3876c2e3af18ec7 (v7.1.0-rc2)