CVE-2023-34256

Name	CVE-2023-34256
Description	An issue was discovered in the Linux kernel before 6.3.3. There is an out-of-bounds read in crc16 in lib/crc16.c when called from fs/ext4/super.c because ext4_group_desc_csum does not properly check an offset. NOTE: this is disputed by third parties because the kernel is not intended to defend against attackers with the stated "When modifying the block device while it is mounted by the filesystem" access.
Source	CVE (at NVD; CERT, ENISA, LWN, oss-sec, fulldisc, Debian ELTS, Red Hat, Ubuntu, Gentoo, SUSE bugzilla/CVE, GitHub advisories/code/issues, web search, more)
References	DLA-3508-1, DLA-3623-1

Vulnerable and fixed packages

The table below lists information on source packages.

Source Package	Release	Version	Status
linux (PTS)	bullseye	5.10.223-1	fixed
	bullseye (security)	5.10.244-1	fixed
	bookworm	6.1.148-1	fixed
	bookworm (security)	6.1.153-1	fixed
	trixie	6.12.43-1	fixed
	trixie (security)	6.12.48-1	fixed
	forky, sid	6.16.12-2	fixed

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

Package	Type	Release	Fixed Version	Urgency	Origin
linux	source	buster	4.19.289-1		DLA-3508-1
linux	source	bullseye	5.10.191-1
linux	source	bookworm	6.1.37-1
linux	source	(unstable)	6.3.7-1	unimportant
linux-5.10	source	buster	5.10.197-1~deb10u1		DLA-3623-1

https://git.kernel.org/linus/4f04351888a83e595571de672e0a4a8b74f4fb31 (6.4-rc2)
Exploitable only when modifying block device while beeing mounted.