# CVE-2026-90013: tracing: Take trace_array reference when opening options file

> A use-after-free in the Linux kernel tracing subsystem allows a local attacker to cause a system crash by racing file operations with instance removal.

- **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:** 16 Sep 2026
- **Updated:** 21 Oct 2026
- **Also known as:** AZL-101486, BELL-CVE-2026-90013, DEBIAN-CVE-2026-90013, GHSA-gwf9-fcmv-qx77, UBUNTU-CVE-2026-90013

## What is CVE-2026-90013?

CVE-2026-90013 is a high-severity use after free vulnerability in Linux, published on 16 Sep 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:

tracing: Take trace_array reference when opening options file

The options files do not take the trace_array reference for the options
they represent. This could cause a use-after-free kernel crash if one of
these files is opened by one task and another task removes the instance
that the option is for. Because it doesn't take a reference upon opening,
it will not stop the removal which will free the options descriptor that
is being used.

As the options are somewhat dynamic in their creation at boot up, each
file represents a flag in the trace_array. The trace_array has an array of
indexes to represent each of these flags that is stored in the
trace_flags_index array. The address of the index array element is used to
pass to the inode->i_private pointer. Then that element is read which
holds the index (which represents the flag) and then the index is used to
calculate the trace_array descriptor from its trace_flags_index array.

One issue is that the index element can not be referenced until the
trace_array's reference is taken. To handle this, create a new helper
function called: trace_array_options_get() that will iterate all the
existing trace_arrays in the ftrace_trace_arrays list (under the
trace_types_lock), and compare the passed in address of the index element
with the entire array of the trace_array's trace_flags_index array.
If it matches, then up the corresponding trace_array's reference and
return.

## Which versions are affected by CVE-2026-90013?


## How do I fix CVE-2026-90013?

Apply the vendor's patch.

## Is CVE-2026-90013 being exploited?

There is no known exploitation of CVE-2026-90013 in the wild and no public exploit code.

## Fix prompt for AI coding agents

```text
Check this codebase for CVE-2026-90013 and fix it if it is affected.

What it is: CVE-2026-90013 is a high-severity use after free vulnerability in Linux, published on 16 Sep 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-2026-90013 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-2026-90013/ (Markdown: https://insights.sbomify.com/CVE-2026-90013/index.md)
```

## Sources

- CVE record: https://www.cve.org/CVERecord?id=CVE-2026-90013
- NVD: https://nvd.nist.gov/vuln/detail/CVE-2026-90013
- OSV: https://osv.dev/vulnerability/CVE-2026-90013

---
From sbomify Insights: https://insights.sbomify.com/CVE-2026-90013/
Summaries are generated and may contain mistakes; the official description above is the record.