# CVE-2026-68146: ftrace: Add global mutex to serialize trace_parser access

> A race condition in the Linux kernel ftrace parser allows local attackers to corrupt state via concurrent writes, potentially causing undefined behavior or denial of service.

- **Severity:** Not scored
- **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:** 10 Aug 2026
- **Updated:** 23 Aug 2026
- **Also known as:** BELL-CVE-2026-68146, DEBIAN-CVE-2026-68146, GHSA-vcpv-vm68-v468, UBUNTU-CVE-2026-68146

## What is CVE-2026-68146?

CVE-2026-68146 is a vulnerability in Linux, published on 10 Aug 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:

ftrace: Add global mutex to serialize trace_parser access

In ftrace, the trace_parser structure is allocated and initialized when
a trace file is opened, and is subsequently used across write and release
handlers to parse user input.

The affected handler paths and their specific functions are:
  - Open paths: ftrace_regex_open(), ftrace_graph_open()
  - Write paths: ftrace_regex_write(), ftrace_graph_write()
  - Release paths: ftrace_regex_release(), ftrace_graph_release()

If userspace opens a trace file descriptor and shares it across multiple
threads, concurrent write calls will race on the parser's internal state,
specifically the 'idx', 'cont', and 'buffer' fields, leading to corrupted
input or undefined behavior.

Fix this by adding a global mutex, parser_lock, to serialize all access
to trace_parser across write and release paths, preventing concurrent
corruption of parser state.

## Which versions are affected by CVE-2026-68146?


## How do I fix CVE-2026-68146?

Apply the vendor's patch.

## Is CVE-2026-68146 being exploited?

There is no known exploitation of CVE-2026-68146 in the wild and no public exploit code.

## Fix prompt for AI coding agents

```text
Check this codebase for CVE-2026-68146 and fix it if it is affected.

What it is: CVE-2026-68146 is a vulnerability in Linux, published on 10 Aug 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-2026-68146 in the wild and no public exploit code.

Affected product: Linux. 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-2026-68146/ (Markdown: https://insights.sbomify.com/CVE-2026-68146/index.md)
```

## Sources

- CVE record: https://www.cve.org/CVERecord?id=CVE-2026-68146
- NVD: https://nvd.nist.gov/vuln/detail/CVE-2026-68146
- OSV: https://osv.dev/vulnerability/CVE-2026-68146

---
From sbomify Insights: https://insights.sbomify.com/CVE-2026-68146/
Summaries are generated and may contain mistakes; the official description above is the record.