# CVE-2025-71312: fs/ntfs3: fix ntfs_mount_options leak in ntfs_fill_super()

> A memory leak in the Linux kernel NTFS3 driver allows local attackers to exhaust kernel memory by repeatedly mounting filesystems, leading to 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:** 27 May 2026
- **Updated:** 26 Oct 2026
- **Also known as:** GHSA-w58m-8mj8-hh8w, UBUNTU-CVE-2025-71312

## What is CVE-2025-71312?

CVE-2025-71312 is a medium-severity denial of service vulnerability in Linux kernel, published on 27 May 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 ntfs_mount_options leak in ntfs_fill_super()

In ntfs_fill_super(), the fc->fs_private pointer is set to NULL without
first freeing the memory it points to. This causes the subsequent call to
ntfs_fs_free() to skip freeing the ntfs_mount_options structure.

This results in a kmemleak report:

  unreferenced object 0xff1100015378b800 (size 32):
    comm "mount", pid 582, jiffies 4294890685
    hex dump (first 32 bytes):
      00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00  ................
      00 00 00 00 00 00 00 00 ed ff ed ff 00 04 00 00  ................
    backtrace (crc ed541d8c):
      __kmalloc_cache_noprof+0x424/0x5a0
      __ntfs_init_fs_context+0x47/0x590
      alloc_fs_context+0x5d8/0x960
      __x64_sys_fsopen+0xb1/0x190
      do_syscall_64+0x50/0x1f0
      entry_SYSCALL_64_after_hwframe+0x76/0x7e

This issue can be reproduced using the following commands:
        fallocate -l 100M test.file
        mount test.file /tmp/test

Since sbi->options is duplicated from fc->fs_private and does not
directly use the memory allocated for fs_private, it is unnecessary to
set fc->fs_private to NULL.

Additionally, this patch simplifies the code by utilizing the helper
function put_mount_options() instead of open-coding the cleanup logic.

Weakness: CWE-401 (Missing Release of Memory after Effective Lifetime)

## Which versions are affected by CVE-2025-71312?

It affects 1 product.


Products: Linux kernel.

## How do I fix CVE-2025-71312?

Apply the vendor's patch.

## Is CVE-2025-71312 being exploited?

There is no known exploitation of CVE-2025-71312 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-2025-71312 and fix it if it is affected.

What it is: CVE-2025-71312 is a medium-severity denial of service vulnerability in Linux kernel, published on 27 May 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-2025-71312 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-2025-71312/ (Markdown: https://insights.sbomify.com/CVE-2025-71312/index.md)
```

## Sources

- CVE record: https://www.cve.org/CVERecord?id=CVE-2025-71312
- NVD: https://nvd.nist.gov/vuln/detail/CVE-2025-71312
- OSV: https://osv.dev/vulnerability/CVE-2025-71312

---
From sbomify Insights: https://insights.sbomify.com/CVE-2025-71312/
Summaries are generated and may contain mistakes; the official description above is the record.