# CVE-2025-40313: ntfs3: pretend $Extend records as regular files

> A flaw in the Linux kernel ntfs3 driver mishandles $Extend records, potentially causing system instability or crashes when accessing specific NTFS structures.

- **Severity:** Not scored
- **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:** 8 Dec 2025
- **Updated:** 11 May 2026
- **Also known as:** BELL-CVE-2025-40313, DEBIAN-CVE-2025-40313, GHSA-2c7r-cgw2-h422, ROOT-OS-DEBIAN-12-CVE-2025-40313, ROOT-OS-DEBIAN-13-CVE-2025-40313, ROOT-OS-UBUNTU-2204-CVE-2025-40313, ROOT-OS-UBUNTU-2404-CVE-2025-40313, UBUNTU-CVE-2025-40313

## What is CVE-2025-40313?

CVE-2025-40313 is a vulnerability in Linux, published on 8 Dec 2025. It can only be exploited from the same machine or local network, with no action from the victim.

### Official description

In the Linux kernel, the following vulnerability has been resolved:

ntfs3: pretend $Extend records as regular files

Since commit af153bb63a33 ("vfs: catch invalid modes in may_open()")
requires any inode be one of S_IFDIR/S_IFLNK/S_IFREG/S_IFCHR/S_IFBLK/
S_IFIFO/S_IFSOCK type, use S_IFREG for $Extend records.

## Which versions are affected by CVE-2025-40313?


## How do I fix CVE-2025-40313?

Apply the vendor's patch.

## Is CVE-2025-40313 being exploited?

There is no known exploitation of CVE-2025-40313 in the wild and no public exploit code.

## Fix prompt for AI coding agents

```text
Check this codebase for CVE-2025-40313 and fix it if it is affected.

What it is: CVE-2025-40313 is a vulnerability in Linux, published on 8 Dec 2025. 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-2025-40313 in the wild and no public exploit code.

Affected product: Linux. 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-2025-40313/ (Markdown: https://insights.sbomify.com/CVE-2025-40313/index.md)
```

## Sources

- CVE record: https://www.cve.org/CVERecord?id=CVE-2025-40313
- NVD: https://nvd.nist.gov/vuln/detail/CVE-2025-40313
- OSV: https://osv.dev/vulnerability/CVE-2025-40313

---
From sbomify Insights: https://insights.sbomify.com/CVE-2025-40313/
Summaries are generated and may contain mistakes; the official description above is the record.