CVE-2026-40706

Name	CVE-2026-40706
Description	In NTFS-3G 2022.10.3 before 2026.2.25, a heap buffer overflow exists in ntfs_build_permissions_posix() in acls.c that allows an attacker to corrupt heap memory in the SUID-root ntfs-3g binary by crafting a malicious NTFS image. The overflow is triggered on the READ path (stat, readdir, open) when processing a security descriptor with multiple ACCESS_DENIED ACEs containing WRITE_OWNER from distinct group SIDs.
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-4544-1, DSA-6221-1

Vulnerable and fixed packages

The table below lists information on source packages.

Source Package	Release	Version	Status
ntfs-3g (PTS)	bullseye	1:2017.3.23AR.3-4+deb11u4	vulnerable
	bullseye (security)	1:2017.3.23AR.3-4+deb11u5	fixed
	bookworm, bookworm (security)	1:2022.10.3-1+deb12u3	fixed
	trixie (security), trixie	1:2022.10.3-5+deb13u1	fixed
	forky, sid	1:2026.2.25-1	fixed

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

Package	Type	Release	Fixed Version	Origin
ntfs-3g	source	bullseye	1:2017.3.23AR.3-4+deb11u5	DLA-4544-1
ntfs-3g	source	bookworm	1:2022.10.3-1+deb12u3	DSA-6221-1
ntfs-3g	source	trixie	1:2022.10.3-5+deb13u1	DSA-6221-1
ntfs-3g	source	(unstable)	1:2026.2.25-1

Notes

https://github.com/tuxera/ntfs-3g/security/advisories/GHSA-4cwv-5285-63v9
Fixed by: https://github.com/tuxera/ntfs-3g/commit/e48e1ef2a1fcff13a590c2224ec21c5bd5d3e92e (2026.2.25)