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.
- 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
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.
Upgrade to the fixed version. Memory-safe languages, compiler hardening and fuzzing prevent most new cases. More about Memory corruption.
Is CVE-2026-93784 being exploited?
There is no known exploitation of CVE-2026-93784 in the wild and no public exploit code.
Sources
Also known as AZL-103670, BELL-CVE-2026-93784, DEBIAN-CVE-2026-93784, GHSA-j7q2-v7q5-76jp, UBUNTU-CVE-2026-93784.