# CVE-2025-71265: fs: ntfs3: fix infinite loop in attr_load_runs_range on inconsistent metadata

> A malformed NTFS image causes an infinite loop in the Linux kernel ntfs3 driver, leading to a denial of service.

- **Severity:** Medium 5.5 (`CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H`)
- **Exploited in the wild:** Not known
- **Login needed:** Any signed-in user
- **Attackable:** Local or same network only
- **Victim action needed:** Not needed
- **Fix available:** Yes
- **Published:** 18 Mar 2026
- **Updated:** 15 Oct 2026
- **Also known as:** AZL-80007, BELL-CVE-2025-71265, DEBIAN-CVE-2025-71265, GHSA-mhc2-234v-x4jm, ROOT-OS-DEBIAN-12-CVE-2025-71265, ROOT-OS-DEBIAN-13-CVE-2025-71265, ROOT-OS-UBUNTU-2204-CVE-2025-71265, ROOT-OS-UBUNTU-2404-CVE-2025-71265, UBUNTU-CVE-2025-71265

## What is CVE-2025-71265?

CVE-2025-71265 is a medium-severity denial of service vulnerability in Linux kernel, published on 18 Mar 2026. 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:

fs: ntfs3: fix infinite loop in attr_load_runs_range on inconsistent metadata

We found an infinite loop bug in the ntfs3 file system that can lead to a
Denial-of-Service (DoS) condition.

A malformed NTFS image can cause an infinite loop when an attribute header
indicates an empty run list, while directory entries reference it as
containing actual data. In NTFS, setting evcn=-1 with svcn=0 is a valid way
to represent an empty run list, and run_unpack() correctly handles this by
checking if evcn + 1 equals svcn and returning early without parsing any run
data. However, this creates a problem when there is metadata inconsistency,
where the attribute header claims to be empty (evcn=-1) but the caller
expects to read actual data. When run_unpack() immediately returns success
upon seeing this condition, it leaves the runs_tree uninitialized with
run->runs as a NULL. The calling function attr_load_runs_range() assumes
that a successful return means that the runs were loaded and sets clen to 0,
expecting the next run_lookup_entry() call to succeed. Because runs_tree
remains uninitialized, run_lookup_entry() continues to fail, and the loop
increments vcn by zero (vcn += 0), leading to an infinite loop.

This patch adds a retry counter to detect when run_lookup_entry() fails
consecutively after attr_load_runs_vcn(). If the run is still not found on
the second attempt, it indicates corrupted metadata and returns -EINVAL,
preventing the Denial-of-Service (DoS) vulnerability.

Weakness: CWE-835 (Loop with Unreachable Exit Condition)

## Which versions are affected by CVE-2025-71265?

It affects 1 product.


Products: Linux kernel.

## How do I fix CVE-2025-71265?

Apply the vendor's patch.

## Is CVE-2025-71265 being exploited?

There is no known exploitation of CVE-2025-71265 in the wild and no public exploit code.

## Other vulnerabilities in Linux kernel

- [CVE-2026-53266](https://insights.sbomify.com/CVE-2026-53266/): Linux Kernel Out-of-Bounds Write (high 8.8, exploited in the wild)
- [CVE-2013-6282](https://insights.sbomify.com/CVE-2013-6282/): Linux Kernel Improper Input Validation (high 8.8, exploited in the wild)
- [CVE-2022-0185](https://insights.sbomify.com/CVE-2022-0185/): Linux Kernel Heap-Based Buffer Overflow (high 8.4, exploited in the wild)
- [CVE-2013-2094](https://insights.sbomify.com/CVE-2013-2094/): Linux Kernel Privilege Escalation (high 8.4, exploited in the wild)
- [CVE-2026-53362](https://insights.sbomify.com/CVE-2026-53362/): Linux Kernel Unspecified (high 7.8, exploited in the wild)

## Fix prompt for AI coding agents

```text
Check this codebase for CVE-2025-71265 and fix it if it is affected.

What it is: CVE-2025-71265 is a medium-severity denial of service vulnerability in Linux kernel, published on 18 Mar 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-2025-71265 in the wild and no public exploit code.

Affected product: Linux kernel. 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-2025-71265/ (Markdown: https://insights.sbomify.com/CVE-2025-71265/index.md)
```

## Sources

- CVE record: https://www.cve.org/CVERecord?id=CVE-2025-71265
- NVD: https://nvd.nist.gov/vuln/detail/CVE-2025-71265
- OSV: https://osv.dev/vulnerability/CVE-2025-71265

---
From sbomify Insights: https://insights.sbomify.com/CVE-2025-71265/
Summaries are generated and may contain mistakes; the official description above is the record.