CVE-2026-89653

Name	CVE-2026-89653
Description	In the Linux kernel, the following vulnerability has been resolved: ceph: reject export_targets ranks >= CEPH_MAX_MDS in mdsmap decode MDSMap export_targets entries are monitor controlled. check_new_map() uses each entry as a bit number in a fixed stack bitmap, so a rank outside the protocol namespace can make set_bit() write past the end of the array. Reject ranks outside CEPH_MAX_MDS while decoding the map. Do not validate against possible_max_rank here because maps may legitimately reference ranks beyond a temporarily reduced max_mds.
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-4817-1, DLA-4841-1, DSA-6528-1

Vulnerable and fixed packages

The table below lists information on source packages.

Source Package	Release	Version	Status
linux (PTS)	bookworm	6.1.176-1	vulnerable
	bookworm (security)	6.1.190-1	fixed
	trixie	6.12.107-1	vulnerable
	trixie (security)	6.12.113-1	fixed
	forky	7.2.11-1	fixed
	sid	7.2.12-1	fixed
linux-6.12 (PTS)	bookworm (security)	6.12.113-1~deb12u1	fixed

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

Package	Type	Release	Fixed Version	Origin
linux	source	bookworm	6.1.190-1	DLA-4841-1
linux	source	trixie	6.12.111-1	DSA-6528-1
linux	source	(unstable)	7.2.6-1
linux-6.12	source	bookworm	6.12.111-1~deb12u1	DLA-4817-1

https://git.kernel.org/linus/aedc9053d909508a5f56c3f49f885fc030df4730 (7.3-rc1)