CVE-2021-3748

Name	CVE-2021-3748
Description	A use-after-free vulnerability was found in the virtio-net device of QEMU. It could occur when the descriptor's address belongs to the non direct access region, due to num_buffers being set after the virtqueue elem has been unmapped. A malicious guest could use this flaw to crash QEMU, resulting in a denial of service condition, or potentially execute code on the host with the privileges of the QEMU process.
Source	CVE (at NVD; CERT, LWN, oss-sec, fulldisc, Red Hat, Ubuntu, Gentoo, SUSE bugzilla/CVE, GitHub advisories/code/issues, web search, more)
References	DLA-2970-1, DLA-3099-1, DSA-4980-1
Debian Bugs	993401

Vulnerable and fixed packages

The table below lists information on source packages.

Source Package	Release	Version	Status
qemu (PTS)	bullseye	1:5.2+dfsg-11+deb11u3	fixed
	bullseye (security)	1:5.2+dfsg-11+deb11u2	fixed
	bookworm	1:7.2+dfsg-7+deb12u7	fixed
	sid, trixie	1:9.1.1+ds-5	fixed

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

Package	Type	Release	Fixed Version	Origin	Debian Bugs
qemu	source	stretch	1:2.8+dfsg-6+deb9u17	DLA-2970-1
qemu	source	buster	1:3.1+dfsg-8+deb10u9	DLA-3099-1
qemu	source	bullseye	1:5.2+dfsg-11+deb11u1	DSA-4980-1
qemu	source	(unstable)	1:6.1+dfsg-6		993401

Notes

https://bugzilla.redhat.com/show_bug.cgi?id=1998514
https://gitlab.com/qemu-project/qemu/-/commit/bedd7e93d01961fcb16a97ae45d93acf357e11f6 (v6.2.0-rc0)
When fixing this issue make sure to not open CVE-2022-26353