# CVE-2026-74661: mac802154: fix netdev use-after-free in beacon worker

> A use-after-free vulnerability in the Linux kernel's mac802154 beacon worker allows attackers to cause denial of service or execute arbitrary code.

- **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:** 22 Aug 2026
- **Updated:** 25 Aug 2026
- **Also known as:** AZL-97263, BELL-CVE-2026-74661, DEBIAN-CVE-2026-74661, GHSA-6r5m-rv77-x5qr, UBUNTU-CVE-2026-74661

## What is CVE-2026-74661?

CVE-2026-74661 is a high-severity use after free vulnerability in Linux, published on 22 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:

mac802154: fix netdev use-after-free in beacon worker

mac802154_beacon_worker() reads local->beacon_req under RCU and derives
the sub-interface from the request, but then drops the RCU read lock and
continues to use both sdata and the embedded wpan_dev.

mac802154_stop_beacons_locked() cancels only pending beacon work, clears
local->beacon_req and frees the request.  A beacon worker that is already
running can therefore continue after interface teardown and dereference
the freed netdev private area.

The scan worker already pins the netdev before leaving RCU.  Apply the
same lifetime rule to the beacon worker: take a netdev reference while
the request is still protected by RCU, and release it on all paths that
continue after the reference is acquired.

## Which versions are affected by CVE-2026-74661?


## How do I fix CVE-2026-74661?

Apply the vendor's patch.

## Is CVE-2026-74661 being exploited?

There is no known exploitation of CVE-2026-74661 in the wild and no public exploit code.

## Fix prompt for AI coding agents

```text
Check this codebase for CVE-2026-74661 and fix it if it is affected.

What it is: CVE-2026-74661 is a high-severity use after free vulnerability in Linux, published on 22 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-2026-74661 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-2026-74661/ (Markdown: https://insights.sbomify.com/CVE-2026-74661/index.md)
```

## Sources

- CVE record: https://www.cve.org/CVERecord?id=CVE-2026-74661
- NVD: https://nvd.nist.gov/vuln/detail/CVE-2026-74661
- OSV: https://osv.dev/vulnerability/CVE-2026-74661

---
From sbomify Insights: https://insights.sbomify.com/CVE-2026-74661/
Summaries are generated and may contain mistakes; the official description above is the record.