# CVE-2024-46845: tracing/timerlat: Only clear timer if a kthread exists

> A use-after-free in the Linux kernel timerlat tracer allows local attackers to potentially execute code or escalate privileges via race conditions during thread shutdown.

- **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:** 27 Sep 2024
- **Updated:** 5 Aug 2026
- **Also known as:** BELL-CVE-2024-46845, DEBIAN-CVE-2024-46845, GHSA-gvp7-4cxg-vpqq, UBUNTU-CVE-2024-46845

## What is CVE-2024-46845?

CVE-2024-46845 is a high-severity use after free vulnerability in Linux kernel, published on 27 Sep 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:

tracing/timerlat: Only clear timer if a kthread exists

The timerlat tracer can use user space threads to check for osnoise and
timer latency. If the program using this is killed via a SIGTERM, the
threads are shutdown one at a time and another tracing instance can start
up resetting the threads before they are fully closed. That causes the
hrtimer assigned to the kthread to be shutdown and freed twice when the
dying thread finally closes the file descriptors, causing a use-after-free
bug.

Only cancel the hrtimer if the associated thread is still around. Also add
the interface_lock around the resetting of the tlat_var->kthread.

Note, this is just a quick fix that can be backported to stable. A real
fix is to have a better synchronization between the shutdown of old
threads and the starting of new ones.

Weakness: CWE-416 (Use After Free)

## Which versions are affected by CVE-2024-46845?

It affects 1 product.


Products: Linux kernel.

## How do I fix CVE-2024-46845?

Apply the vendor's patch.

## Is CVE-2024-46845 being exploited?

There is no known exploitation of CVE-2024-46845 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-2024-46845 and fix it if it is affected.

What it is: CVE-2024-46845 is a high-severity use after free vulnerability in Linux kernel, published on 27 Sep 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-2024-46845 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-2024-46845/ (Markdown: https://insights.sbomify.com/CVE-2024-46845/index.md)
```

## Sources

- CVE record: https://www.cve.org/CVERecord?id=CVE-2024-46845
- NVD: https://nvd.nist.gov/vuln/detail/CVE-2024-46845
- OSV: https://osv.dev/vulnerability/CVE-2024-46845

---
From sbomify Insights: https://insights.sbomify.com/CVE-2024-46845/
Summaries are generated and may contain mistakes; the official description above is the record.