# CVE-2026-98183: wifi: mac80211: avoid out-of-bounds read for empty PREQ elements

> An out-of-bounds read in the Linux kernel's mac80211 module allows attackers to cause a denial of service or leak information via crafted Wi-Fi mesh 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:** 6 Oct 2026
- **Updated:** 19 Oct 2026
- **Also known as:** DEBIAN-CVE-2026-98183, GHSA-867h-2x92-cj79, UBUNTU-CVE-2026-98183

## What is CVE-2026-98183?

CVE-2026-98183 is a memory corruption vulnerability in Linux, published on 6 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: avoid out-of-bounds read for empty PREQ elements

ieee80211_mesh_preq_size_ok() derives the location of the PREQ bottom
fields before checking whether the element contains even the fixed
header. ieee80211_mesh_hwmp_preq_get_bottom() reads the flags byte to
account for the optional Address Extension field. Consequently, an
empty PREQ element causes a one-byte read beyond its declared payload.

Move the helper call after both size checks, so the bottom fields are
only accessed when they are present.

## Which versions are affected by CVE-2026-98183?


## How do I fix CVE-2026-98183?

Apply the vendor's patch.

## Is CVE-2026-98183 being exploited?

There is no known exploitation of CVE-2026-98183 in the wild and no public exploit code.

## Fix prompt for AI coding agents

```text
Check this codebase for CVE-2026-98183 and fix it if it is affected.

What it is: CVE-2026-98183 is a memory corruption vulnerability in Linux, published on 6 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-2026-98183 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-2026-98183/ (Markdown: https://insights.sbomify.com/CVE-2026-98183/index.md)
```

## Sources

- CVE record: https://www.cve.org/CVERecord?id=CVE-2026-98183
- NVD: https://nvd.nist.gov/vuln/detail/CVE-2026-98183
- OSV: https://osv.dev/vulnerability/CVE-2026-98183

---
From sbomify Insights: https://insights.sbomify.com/CVE-2026-98183/
Summaries are generated and may contain mistakes; the official description above is the record.