CVE-2023-3354

Name	CVE-2023-3354
Description	A flaw was found in the QEMU built-in VNC server. When a client connects to the VNC server, QEMU checks whether the current number of connections crosses a certain threshold and if so, cleans up the previous connection. If the previous connection happens to be in the handshake phase and fails, QEMU cleans up the connection again, resulting in a NULL pointer dereference issue. This could allow a remote unauthenticated client to cause a denial of service.
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-3759-1

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	vulnerable
	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
qemu	source	buster	1:3.1+dfsg-8+deb10u12	DLA-3759-1
qemu	source	bullseye	1:5.2+dfsg-11+deb11u3
qemu	source	bookworm	1:7.2+dfsg-7+deb12u2
qemu	source	(unstable)	1:8.0.4+dfsg-1

Notes

https://bugzilla.redhat.com/show_bug.cgi?id=2216478
https://lists.nongnu.org/archive/html/qemu-devel/2023-07/msg01014.html
Fixed by: https://gitlab.com/qemu-project/qemu/-/commit/5300472ec0990c61742d89b5eea1c1e6941f6d62 (v8.0.4)