# CVE-2026-93784: wifi: cfg80211: validate IEs in cfg80211_wext_siwgenie()

> A local attacker can trigger a kernel crash via malformed WiFi Information Elements, causing a denial of service in the Linux kernel.

- **Severity:** Not scored
- **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:** 24 Sep 2026
- **Updated:** 3 Oct 2026
- **Also known as:** AZL-103670, BELL-CVE-2026-93784, DEBIAN-CVE-2026-93784, GHSA-j7q2-v7q5-76jp, UBUNTU-CVE-2026-93784

## What is CVE-2026-93784?

CVE-2026-93784 is a memory corruption vulnerability in Linux, published on 24 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:

wifi: cfg80211: validate IEs in cfg80211_wext_siwgenie()

The KASAN allocation trace shows that a malformed IE buffer is
stored via SIOCSIWGENIE (cfg80211_wext_siwgenie()) without any
validation. The crash trace shows that a subsequent SIOCSIWESSID
triggers a connection attempt which calls cfg80211_sme_get_conn_ies()
to process the stored IE buffer, causing:

 - An out-of-bounds read in skip_ie() which reads ies[pos+1]
   (the length byte) past the end of the 1-byte buffer.

 - An integer underflow in the memcpy size argument when offs
   returned by ieee80211_ie_split() exceeds ies_len, causing
   unsigned subtraction to wrap to SIZE_MAX and triggering a
   fortify panic.

Fix this by validating the IE buffer in cfg80211_wext_siwgenie()
before storing it.

[drop unnecessary ie_len check, update commit message]

## Which versions are affected by CVE-2026-93784?


## How do I fix CVE-2026-93784?

Apply the vendor's patch.

## Is CVE-2026-93784 being exploited?

There is no known exploitation of CVE-2026-93784 in the wild and no public exploit code.

## Fix prompt for AI coding agents

```text
Check this codebase for CVE-2026-93784 and fix it if it is affected.

What it is: CVE-2026-93784 is a memory corruption vulnerability in Linux, published on 24 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-2026-93784 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-2026-93784/ (Markdown: https://insights.sbomify.com/CVE-2026-93784/index.md)
```

## Sources

- CVE record: https://www.cve.org/CVERecord?id=CVE-2026-93784
- NVD: https://nvd.nist.gov/vuln/detail/CVE-2026-93784
- OSV: https://osv.dev/vulnerability/CVE-2026-93784

---
From sbomify Insights: https://insights.sbomify.com/CVE-2026-93784/
Summaries are generated and may contain mistakes; the official description above is the record.