Hello oss-security,
A vulnerability in ntfs-3g (https://github.com/tuxera/ntfs-3g) has been
reported to us by a third party.
Short description:
In NTFS-3G 2022.10.3, 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.
CVSS 3.1: 7.8 (High) — AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H
References:
CVE ID: CVE-2026-40706
Full advisory:
https://github.com/tuxera/ntfs-3g/security/advisories/GHSA-4cwv-5285-63v9
Fixed version: https://github.com/tuxera/ntfs-3g/releases/tag/2026.2.25
Credits: reported by Andrea Bocchetti
