# CVE-2024-53690: nilfs2: prevent use of deleted inode

> A use-after-free vulnerability in the nilfs2 filesystem allows local attackers to trigger a kernel warning and potential denial of service via corrupted inode bitmaps.

- **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:** 11 Jan 2025
- **Updated:** 11 May 2026
- **Also known as:** BELL-CVE-2024-53690, DEBIAN-CVE-2024-53690, GHSA-497m-9xj2-rmhf, UBUNTU-CVE-2024-53690

## What is CVE-2024-53690?

CVE-2024-53690 is a medium-severity use after free vulnerability in Linux kernel, published on 11 Jan 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:

nilfs2: prevent use of deleted inode

syzbot reported a WARNING in nilfs_rmdir. [1]

Because the inode bitmap is corrupted, an inode with an inode number that
should exist as a ".nilfs" file was reassigned by nilfs_mkdir for "file0",
causing an inode duplication during execution.  And this causes an
underflow of i_nlink in rmdir operations.

The inode is used twice by the same task to unmount and remove directories
".nilfs" and "file0", it trigger warning in nilfs_rmdir.

Avoid to this issue, check i_nlink in nilfs_iget(), if it is 0, it means
that this inode has been deleted, and iput is executed to reclaim it.

[1]
WARNING: CPU: 1 PID: 5824 at fs/inode.c:407 drop_nlink+0xc4/0x110 fs/inode.c:407
...
Call Trace:
 <TASK>
 nilfs_rmdir+0x1b0/0x250 fs/nilfs2/namei.c:342
 vfs_rmdir+0x3a3/0x510 fs/namei.c:4394
 do_rmdir+0x3b5/0x580 fs/namei.c:4453
 __do_sys_rmdir fs/namei.c:4472 [inline]
 __se_sys_rmdir fs/namei.c:4470 [inline]
 __x64_sys_rmdir+0x47/0x50 fs/namei.c:4470
 do_syscall_x64 arch/x86/entry/common.c:52 [inline]
 do_syscall_64+0xf3/0x230 arch/x86/entry/common.c:83
 entry_SYSCALL_64_after_hwframe+0x77/0x7f

## Which versions are affected by CVE-2024-53690?

It affects 1 product.


Products: Linux kernel.

## How do I fix CVE-2024-53690?

Apply the vendor's patch.

## Is CVE-2024-53690 being exploited?

There is no known exploitation of CVE-2024-53690 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-2024-53690 and fix it if it is affected.

What it is: CVE-2024-53690 is a medium-severity use after free vulnerability in Linux kernel, published on 11 Jan 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-2024-53690 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-2024-53690/ (Markdown: https://insights.sbomify.com/CVE-2024-53690/index.md)
```

## Sources

- CVE record: https://www.cve.org/CVERecord?id=CVE-2024-53690
- NVD: https://nvd.nist.gov/vuln/detail/CVE-2024-53690
- OSV: https://osv.dev/vulnerability/CVE-2024-53690

---
From sbomify Insights: https://insights.sbomify.com/CVE-2024-53690/
Summaries are generated and may contain mistakes; the official description above is the record.
