CVE-2026-23040 wifi: mac80211_hwsim: fix typo in frequency notification
A typo in the Linux kernel's mac80211_hwsim module causes a NULL pointer dereference, leading to a denial of service.
- Exploited in the wild
- Not known
- Login needed
- Not needed
- Attackable
- Local or same network only
- Victim action needed
- Not needed
- Fix
- Available
What is CVE-2026-23040?
CVE-2026-23040 is a vulnerability in Linux, published on 4 Feb 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_hwsim: fix typo in frequency notification
The NAN notification is for 5745 MHz which corresponds to channel 149 and not 5475 which is not actually a valid channel. This could result in a NULL pointer dereference in cfg80211_next_nan_dw_notif.
Which versions are affected by CVE-2026-23040?
How do I fix CVE-2026-23040?
Apply the vendor's patch.
Is CVE-2026-23040 being exploited?
There is no known exploitation of CVE-2026-23040 in the wild and no public exploit code.
Sources
Also known as BELL-CVE-2026-23040, DEBIAN-CVE-2026-23040, GHSA-4mqx-ggc6-9qj3, UBUNTU-CVE-2026-23040.