# CVE-2024-53143: fsnotify: Fix ordering of iput() and watched_objects decrement

> A use-after-free vulnerability in the Linux kernel's fsnotify subsystem allows attackers to potentially execute code or cause a denial of service.

- **Severity:** High 7.8 (`CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/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:** 7 Dec 2024
- **Updated:** 5 Aug 2026
- **Also known as:** BELL-CVE-2024-53143, DEBIAN-CVE-2024-53143, GHSA-rfr4-95g9-6vf3, UBUNTU-CVE-2024-53143

## What is CVE-2024-53143?

CVE-2024-53143 is a high-severity use after free vulnerability in Linux kernel, published on 7 Dec 2024. 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:

fsnotify: Fix ordering of iput() and watched_objects decrement

Ensure the superblock is kept alive until we're done with iput().
Holding a reference to an inode is not allowed unless we ensure the
superblock stays alive, which fsnotify does by keeping the
watched_objects count elevated, so iput() must happen before the
watched_objects decrement.
This can lead to a UAF of something like sb->s_fs_info in tmpfs, but the
UAF is hard to hit because race orderings that oops are more likely, thanks
to the CHECK_DATA_CORRUPTION() block in generic_shutdown_super().

Also, ensure that fsnotify_put_sb_watched_objects() doesn't call
fsnotify_sb_watched_objects() on a superblock that may have already been
freed, which would cause a UAF read of sb->s_fsnotify_info.

Weakness: CWE-416 (Use After Free)

## Which versions are affected by CVE-2024-53143?

It affects 1 product.


Products: Linux kernel.

## How do I fix CVE-2024-53143?

Apply the vendor's patch.

## Is CVE-2024-53143 being exploited?

There is no known exploitation of CVE-2024-53143 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-2024-53143 and fix it if it is affected.

What it is: CVE-2024-53143 is a high-severity use after free vulnerability in Linux kernel, published on 7 Dec 2024. 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-2024-53143 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-2024-53143/ (Markdown: https://insights.sbomify.com/CVE-2024-53143/index.md)
```

## Sources

- CVE record: https://www.cve.org/CVERecord?id=CVE-2024-53143
- NVD: https://nvd.nist.gov/vuln/detail/CVE-2024-53143
- OSV: https://osv.dev/vulnerability/CVE-2024-53143

---
From sbomify Insights: https://insights.sbomify.com/CVE-2024-53143/
Summaries are generated and may contain mistakes; the official description above is the record.