CVE-2026-40706
What it is
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.
At a glance
- Exploitability
- Can be exploited locally on the machine without logging in. High risk of data exposure, data tampering, service disruption.
- Exploit odds
- 0.2% chance of exploitation in the next 30 days (EPSS).
- Fix
- A patch, advisory or fixed version is referenced. Upgrade or apply it.
Timeline
- PublishedDisclosed publicly on CVE.org and NVD
- Last updatedMost recent change to the record
Why it ranks here
- Exploited in the wild: no, CISA does not list it.
- Exploit odds: 0.2% in the next 30 days (EPSS).
- Severity: 8.4 HIGH (CVSS).
- Fix: a patch or advisory is linked.
Details
- Published
- Last modified
- Exploit probability
- 0.2% · EPSS, next 30 days
- Weakness
- CWE-122
- Record status
- Awaiting Analysis
Attack profile CVSS 3.1 · 8.4
- Attack vector
- Local
- Complexity
- Low
- Privileges needed
- None
- User interaction
- None
- Scope
- Unchanged
- Confidentiality
- High
- Integrity
- High
- Availability
- High
Raw vector
CVSS:3.1/AV:L/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H
Is it in your code?
Hand this to your coding agent. It searches your project for the affected products and checks versions. Nothing leaves your machine.
Read https://cve-list.com/agent/cve/CVE-2026-40706.md and follow it. Check whether this project is affected by CVE-2026-40706. Read only. Don't change anything and don't upload my code. Tell me yes, no or not sure, with the file as proof.
Fix and advisories
- https://github.com/tuxera/ntfs-3g/releases/tag/2026.2.25
- https://github.com/tuxera/ntfs-3g/security/advisories/GHSA-4cwv-5285-63v9
References
- https://github.com/tuxera/ntfs-3g/blob/d3ace19838ce37cfde55294e76841e6d2f393f9e/libntfs-3g/acls.c#L4011-L4027
- https://github.com/tuxera/ntfs-3g/releases/tag/2026.2.25
- https://github.com/tuxera/ntfs-3g/security/advisories/GHSA-4cwv-5285-63v9
- https://www.openwall.com/lists/oss-security/2026/04/21/4
- http://www.openwall.com/lists/oss-security/2026/04/21/4
- https://lists.debian.org/debian-lts-announce/2026/04/msg00024.html