CVE-2025-40066 wifi: mt76: mt7996: Check phy before init msta_link in mt7996_mac_sta_add_links()
A missing null check in the mt7996 WiFi driver can cause a kernel crash, leading to denial of service for local or adjacent attackers.
- 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-2025-40066?
CVE-2025-40066 is a vulnerability in Linux, published on 28 Oct 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: mt76: mt7996: Check phy before init msta_link in mt7996_mac_sta_add_links()
In order to avoid a possible NULL pointer dereference in mt7996_mac_sta_init_link routine, move the phy pointer check before running mt7996_mac_sta_init_link() in mt7996_mac_sta_add_links routine.
Which versions are affected by CVE-2025-40066?
How do I fix CVE-2025-40066?
Apply the vendor's patch.
Is CVE-2025-40066 being exploited?
There is no known exploitation of CVE-2025-40066 in the wild and no public exploit code.
Sources
Also known as BELL-CVE-2025-40066, DEBIAN-CVE-2025-40066, GHSA-8r3f-48gc-phmq, UBUNTU-CVE-2025-40066.