CVE-2024-31080

Name	CVE-2024-31080
Description	A heap-based buffer over-read vulnerability was found in the X.org server's ProcXIGetSelectedEvents() function. This issue occurs when byte-swapped length values are used in replies, potentially leading to memory leakage and segmentation faults, particularly when triggered by a client with a different endianness. This vulnerability could be exploited by an attacker to cause the X server to read heap memory values and then transmit them back to the client until encountering an unmapped page, resulting in a crash. Despite the attacker's inability to control the specific memory copied into the replies, the small length values typically stored in a 32-bit integer can result in significant attempted out-of-bounds reads.
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-3787-1, DSA-5657-1

Vulnerable and fixed packages

The table below lists information on source packages.

Source Package	Release	Version	Status
xorg-server (PTS)	bullseye	2:1.20.11-1+deb11u13	fixed
	bullseye (security)	2:1.20.11-1+deb11u14	fixed
	bookworm, bookworm (security)	2:21.1.7-3+deb12u8	fixed
	trixie	2:21.1.14-1	fixed
	sid	2:21.1.14-2	fixed
xwayland (PTS)	bookworm	2:22.1.9-1	vulnerable
	sid, trixie	2:24.1.4-1	fixed

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

Package	Type	Release	Fixed Version	Origin
xorg-server	source	buster	2:1.20.4-1+deb10u14	DLA-3787-1
xorg-server	source	bullseye	2:1.20.11-1+deb11u13	DSA-5657-1
xorg-server	source	bookworm	2:21.1.7-3+deb12u7	DSA-5657-1
xorg-server	source	(unstable)	2:21.1.11-3
xwayland	source	(unstable)	2:23.2.6-1

Notes

[bookworm] - xwayland <ignored> (Minor issue; Xwayland shouldn't be running as root)
Fixed by: https://gitlab.freedesktop.org/xorg/xserver/-/commit/96798fc1967491c80a4d0c8d9e0a80586cb2152b
https://lists.x.org/archives/xorg-announce/2024-April/003497.html