# CVE-2026-81010: io_uring/waitid: honor task_work cancellation

> A race condition in the Linux kernel io_uring waitid handler allows incorrect task context execution, potentially leading to undefined behavior or crashes.

- **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:** 11 Sep 2026
- **Updated:** 19 Oct 2026
- **Also known as:** BELL-CVE-2026-81010, DEBIAN-CVE-2026-81010, GHSA-qqff-gjp9-r6f6, UBUNTU-CVE-2026-81010

## What is CVE-2026-81010?

CVE-2026-81010 is a high-severity vulnerability in Linux, published on 11 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:

io_uring/waitid: honor task_work cancellation

io_waitid_cb() may run through the fallback task_work path when
task_work_add() can no longer queue work to the originating task. The
fallback runs from a kworker and io_uring marks such task work as
canceled through tw.cancel.

io_waitid_cb() currently ignores tw.cancel and calls __do_wait().
waitid is task-context dependent: __do_wait() performs child lookup
relative to current, and the retry path also uses
current->signal->wait_chldexit. If the callback runs from the fallback
kworker, current is therefore not the task that submitted the request.

Honor tw.cancel before entering __do_wait(). Complete the request with
-ECANCELED and skip the siginfo copy, since canceled task work may run
without the submitting task's userspace execution context.

Keep the existing siginfo handling for normal waitid completion and
explicit cancellation.

## Which versions are affected by CVE-2026-81010?


## How do I fix CVE-2026-81010?

Apply the vendor's patch.

## Is CVE-2026-81010 being exploited?

There is no known exploitation of CVE-2026-81010 in the wild and no public exploit code.

## Fix prompt for AI coding agents

```text
Check this codebase for CVE-2026-81010 and fix it if it is affected.

What it is: CVE-2026-81010 is a high-severity vulnerability in Linux, published on 11 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-2026-81010 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-2026-81010/ (Markdown: https://insights.sbomify.com/CVE-2026-81010/index.md)
```

## Sources

- CVE record: https://www.cve.org/CVERecord?id=CVE-2026-81010
- NVD: https://nvd.nist.gov/vuln/detail/CVE-2026-81010
- OSV: https://osv.dev/vulnerability/CVE-2026-81010

---
From sbomify Insights: https://insights.sbomify.com/CVE-2026-81010/
Summaries are generated and may contain mistakes; the official description above is the record.