# CVE-2026-98708: wifi: mac80211: keep paired old chanctx alive

> A use-after-free in the Linux kernel Wi-Fi subsystem allows attackers to cause denial of service or potentially execute code via crafted wireless operations.

- **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-108608, BELL-CVE-2026-98708, DEBIAN-CVE-2026-98708, GHSA-84vh-fqvc-p664, UBUNTU-CVE-2026-98708

## What is CVE-2026-98708?

CVE-2026-98708 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: keep paired old chanctx alive

An in-place replacement keeps reciprocal replace_ctx pointers between
the old WILL_BE_REPLACED chanctx and the new REPLACES_OTHER chanctx.
However, the early free paths only consider assigned and reserved link
users when deciding whether to free the old chanctx.

That lets the old chanctx be freed too early while the replacement
partner still points back to it, either when the last assigned link is
released or when that link successfully reassigns to another existing
context. Later unreserve and switch-finalization paths can then follow a
stale replace_ctx pointer.

Keep a paired old chanctx alive until the replacement pair has been torn
down. Apply the same check to both __ieee80211_link_release_channel()
and ieee80211_link_use_reserved_reassign(). If the replacement is later
abandoned, ieee80211_link_unreserve_chanctx() already tears down the
pairing before freeing the old chanctx once no users remain.

## Which versions are affected by CVE-2026-98708?


## How do I fix CVE-2026-98708?

Apply the vendor's patch.

## Is CVE-2026-98708 being exploited?

There is no known exploitation of CVE-2026-98708 in the wild and no public exploit code.

## Fix prompt for AI coding agents

```text
Check this codebase for CVE-2026-98708 and fix it if it is affected.

What it is: CVE-2026-98708 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-2026-98708 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-2026-98708/ (Markdown: https://insights.sbomify.com/CVE-2026-98708/index.md)
```

## Sources

- CVE record: https://www.cve.org/CVERecord?id=CVE-2026-98708
- NVD: https://nvd.nist.gov/vuln/detail/CVE-2026-98708
- OSV: https://osv.dev/vulnerability/CVE-2026-98708

---
From sbomify Insights: https://insights.sbomify.com/CVE-2026-98708/
Summaries are generated and may contain mistakes; the official description above is the record.