# CVE-2026-98707: wifi: mac80211: shut down RX BA session timer on teardown

> A use-after-free in the Linux kernel WiFi driver allows attackers to execute code or cause denial of service via crafted WiFi frames.

- **Severity:** Not scored
- **Exploited in the wild:** Not known
- **Login needed:** Not needed
- **Attackable:** Local or same network only
- **Victim action needed:** Not needed
- **Fix available:** Yes
- **Published:** 18 Oct 2026
- **Updated:** 21 Oct 2026
- **Also known as:** AZL-108690, BELL-CVE-2026-98707, DEBIAN-CVE-2026-98707, GHSA-8mvq-3rmc-c8vm, UBUNTU-CVE-2026-98707

## What is CVE-2026-98707?

CVE-2026-98707 is an use after free vulnerability in Linux, published on 18 Oct 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:

wifi: mac80211: shut down RX BA session timer on teardown

Tearing down an RX BA session can leave the session timer queued on a
freed tid_rx. Later timer-wheel processing and the timer callback itself
then run against freed memory.

An RX BAR handler can dereference tid_rx under RCU before teardown
unpublishes it and stay in its read-side critical section while teardown
deletes the session timer. The stale handler can then rearm the timer
after timer_delete_sync() returns and before the RCU callback frees
tid_rx.

Use timer_shutdown_sync() so rearm attempts become ineffective once
teardown starts. Keep reorder_timer unchanged: teardown marks the session
removed under reorder_lock and its release path checks that state before
rearming. session_timer has no equivalent guard because
ieee80211_rx_h_ctrl() rearms it before taking reorder_lock.

## Which versions are affected by CVE-2026-98707?


## How do I fix CVE-2026-98707?

Apply the vendor's patch.

## Is CVE-2026-98707 being exploited?

There is no known exploitation of CVE-2026-98707 in the wild and no public exploit code.

## Fix prompt for AI coding agents

```text
Check this codebase for CVE-2026-98707 and fix it if it is affected.

What it is: CVE-2026-98707 is an use after free vulnerability in Linux, published on 18 Oct 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-2026-98707 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-2026-98707/ (Markdown: https://insights.sbomify.com/CVE-2026-98707/index.md)
```

## Sources

- CVE record: https://www.cve.org/CVERecord?id=CVE-2026-98707
- NVD: https://nvd.nist.gov/vuln/detail/CVE-2026-98707
- OSV: https://osv.dev/vulnerability/CVE-2026-98707

---
From sbomify Insights: https://insights.sbomify.com/CVE-2026-98707/
Summaries are generated and may contain mistakes; the official description above is the record.