# CVE-2026-40706: Memory corruption in NTFS-3G

> Heap buffer overflow in NTFS-3G allows attackers to execute arbitrary code with root privileges via a malicious NTFS image.

- **Severity:** High 8.4 (`CVSS:3.1/AV:L/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H`)
- **Exploited in the wild:** Not known
- **Login needed:** Not needed
- **Attackable:** Local or same network only
- **Victim action needed:** Not needed
- **Fix available:** Yes
- **Published:** 21 Apr 2026
- **Updated:** 22 Apr 2026
- **Also known as:** ALPINE-CVE-2026-40706, AZL-83181, DEBIAN-CVE-2026-40706, GHSA-4cwv-5285-63v9, MGASA-2026-0118, OESA-2026-2100, OESA-2026-2101, OESA-2026-2102, OESA-2026-2103, OESA-2026-2104, SUSE-SU-2026:1571-1, SUSE-SU-2026:21432-1, UBUNTU-CVE-2026-40706, USN-8192-2, openSUSE-SU-2026:10614-1, openSUSE-SU-2026:20651-1

## What is CVE-2026-40706?

CVE-2026-40706 is a high-severity memory corruption vulnerability in Tuxera NTFS-3G, published on 21 Apr 2026. It can only be exploited from the same machine or local network, with no action from the victim.

### Official 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.

Weakness: CWE-122 (Heap-based Buffer Overflow)

## Which versions are affected by CVE-2026-40706?


| Package | Ecosystem | Affected | Fixed in |
| --- | --- | --- | --- |
| `ntfs-3g_ntfsprogs` | SUSE:Linux Enterprise Module for Basesystem 15 SP7 | All versions | 2022.5.17-150000.3.24.1 |
| `ntfs-3g_ntfsprogs` | SUSE:Linux Enterprise Module for Development Tools 15 SP7 | All versions | 2022.5.17-150000.3.24.1 |
| `ntfs-3g_ntfsprogs` | SUSE:Linux Enterprise Server 15 SP6-LTSS | All versions | 2022.5.17-150000.3.24.1 |
| `ntfs-3g_ntfsprogs` | SUSE:Linux Enterprise Server for SAP Applications 15 SP6 | All versions | 2022.5.17-150000.3.24.1 |
| `ntfs-3g_ntfsprogs` | openSUSE:Tumbleweed | All versions | 2022.10.3-6.1 |

## How do I fix CVE-2026-40706?

Upgrade to a fixed version.

## Is CVE-2026-40706 being exploited?

There is no known exploitation of CVE-2026-40706 in the wild and no public exploit code.

## Fix prompt for AI coding agents

```text
Check this codebase for CVE-2026-40706 and fix it if it is affected.

What it is: CVE-2026-40706 is a high-severity memory corruption vulnerability in Tuxera NTFS-3G, published on 21 Apr 2026. It can only be exploited from the same machine or local network, with no action from the victim.
Exploitation: There is no known exploitation of CVE-2026-40706 in the wild and no public exploit code.

Affected product: Tuxera NTFS-3G. No package-level version data is available, so check the vendor advisory linked from the reference page.

Task:
1. Search the dependency manifests and lockfiles (for example package.json, package-lock.json, requirements.txt, poetry.lock, uv.lock, pom.xml, build.gradle, go.mod, Cargo.lock, Gemfile.lock) and any Dockerfiles for the affected packages, including transitive dependencies.
2. If an affected version is in use, upgrade it to the fixed version for its release line with the project's package manager, so the lockfile is regenerated. Prefer the smallest upgrade that fixes it.
3. If there is no fix, or the upgrade would break the build, do not guess: explain the risk and the safest workaround instead.
4. Run the tests and summarise what changed and why.
5. If nothing in the project is affected, say so and change nothing.

Reference: https://insights.sbomify.com/CVE-2026-40706/ (Markdown: https://insights.sbomify.com/CVE-2026-40706/index.md)
```

## Sources

- CVE record: https://www.cve.org/CVERecord?id=CVE-2026-40706
- NVD: https://nvd.nist.gov/vuln/detail/CVE-2026-40706
- OSV: https://osv.dev/vulnerability/CVE-2026-40706

---
From sbomify Insights: https://insights.sbomify.com/CVE-2026-40706/
Summaries are generated and may contain mistakes; the official description above is the record.