CVE-2026-98331 wifi: mac80211: unlist vifs when their netdev is unregistered
A null pointer dereference in the Linux kernel mac80211 subsystem allows local attackers to cause a system crash by triggering specific network namespace cleanup failures.
- 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-2026-98331?
CVE-2026-98331 is a high-severity vulnerability in Linux, published on 6 Oct 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: unlist vifs when their netdev is unregistered
mac80211 only removes vifs from the local->interfaces list when an interface is removed via ieee80211_if_remove(), before it unregisters the netdev. However, it's possible for a netdev to be unregistered without going through that: When the netns that holds the wiphy is destroyed, the wiphy is supposed to move to the init_ns, but that can run into allocation failures.
Then, mac80211 has an interface listed that doesn't exist, and will eventually hit
BUG: failure at net/wireless/core.h:141/wiphy_to_rdev()! ... _cfg80211_unregister_wdev+0x24/0x36a [cfg80211] cfg80211_unregister_wdev+0x15/0x1d [cfg80211] ieee80211_remove_interfaces+0x1ff/0x257 [mac80211] ieee80211_unregister_hw+0x73/0x1d1 [mac80211] mac80211_hwsim_del_radio+0x114/0x166 [mac80211_hwsim]
Remove the interface from the list in ->ndo_uninit if it's still around to avoid this.
Which versions are affected by CVE-2026-98331?
How do I fix CVE-2026-98331?
Apply the vendor's patch.
Is CVE-2026-98331 being exploited?
There is no known exploitation of CVE-2026-98331 in the wild and no public exploit code.
Sources
Also known as AZL-106347, BELL-CVE-2026-98331, DEBIAN-CVE-2026-98331, GHSA-wm55-5w39-6wj2, UBUNTU-CVE-2026-98331.