# CVE-2024-57940: exfat: fix the infinite loop in exfat_readdir()

> A corrupted exFAT filesystem can cause an infinite loop in the Linux kernel, leading to a system hang and 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:** 21 Jan 2025
- **Updated:** 15 Oct 2026
- **Also known as:** AZL-55904, AZL-55910, BELL-CVE-2024-57940, DEBIAN-CVE-2024-57940, GHSA-8pw9-7gv3-535c, UBUNTU-CVE-2024-57940

## What is CVE-2024-57940?

CVE-2024-57940 is a medium-severity denial of service vulnerability in Linux kernel, published on 21 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:

exfat: fix the infinite loop in exfat_readdir()

If the file system is corrupted so that a cluster is linked to
itself in the cluster chain, and there is an unused directory
entry in the cluster, 'dentry' will not be incremented, causing
condition 'dentry < max_dentries' unable to prevent an infinite
loop.

This infinite loop causes s_lock not to be released, and other
tasks will hang, such as exfat_sync_fs().

This commit stops traversing the cluster chain when there is unused
directory entry in the cluster to avoid this infinite loop.

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

## Which versions are affected by CVE-2024-57940?

It affects 1 product.


Products: Linux kernel.

## How do I fix CVE-2024-57940?

Apply the vendor's patch.

## Is CVE-2024-57940 being exploited?

There is no known exploitation of CVE-2024-57940 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-2024-57940 and fix it if it is affected.

What it is: CVE-2024-57940 is a medium-severity denial of service vulnerability in Linux kernel, published on 21 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-2024-57940 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-2024-57940/ (Markdown: https://insights.sbomify.com/CVE-2024-57940/index.md)
```

## Sources

- CVE record: https://www.cve.org/CVERecord?id=CVE-2024-57940
- NVD: https://nvd.nist.gov/vuln/detail/CVE-2024-57940
- OSV: https://osv.dev/vulnerability/CVE-2024-57940

---
From sbomify Insights: https://insights.sbomify.com/CVE-2024-57940/
Summaries are generated and may contain mistakes; the official description above is the record.