CVE-2025-38642 wifi: mac80211: fix WARN_ON for monitor mode on some devices
A kernel warning triggered by monitor mode on specific Wi-Fi devices can cause a denial of service, requiring a patch for affected Linux kernels.
- 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-2025-38642?
CVE-2025-38642 is a medium-severity denial of service vulnerability in Linux kernel, published on 22 Aug 2025. 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: fix WARN_ON for monitor mode on some devices
On devices without WANT_MONITOR_VIF (and probably without channel context support) we get a WARN_ON for changing the per-link setting of a monitor interface.
Since we already skip AP_VLAN interfaces and MONITOR with WANT_MONITOR_VIF and/or NO_VIRTUAL_MONITOR should update the settings, catch this in the link change code instead of the warning.
Weakness: CWE-617
Which versions are affected by CVE-2025-38642?
It affects 1 product.
Products include Linux kernel.
How do I fix CVE-2025-38642?
Apply the vendor's patch.
Upgrade, then put limits on request size, rate and nesting depth so one client cannot exhaust the service. More about Denial of service.
Is CVE-2025-38642 being exploited?
There is no known exploitation of CVE-2025-38642 in the wild and no public exploit code.
Other vulnerabilities in Linux kernel
Sources
Also known as BELL-CVE-2025-38642, GHSA-jw44-xqgm-jxvc, UBUNTU-CVE-2025-38642.