CVE-2026-93804 wifi: mac80211: ibss: wait for in-flight TX on disconnect
A race condition in Linux kernel IBSS disconnect handling can cause driver confusion and potential 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-2026-93804?
CVE-2026-93804 is a 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: mac80211: ibss: wait for in-flight TX on disconnect
While leaving an IBSS in ieee80211_ibss_disconnect() mac80211 flushes stations, turns the carrier off and immediately tells the driver to leave as well. While there may be synchronize_net() in station flush and in this code later, packets can still be transmitted due to cross-CPU race conditions after carrier off is set. Therefore, it's possible for a race to happen where a TX to the driver occurs while or after telling it to leave the IBSS. This can be confusing to drivers, and in the case of iwlwifi leads to an attempt to use invalid queues.
Move netif_carrier_off() to occur before sta_info_flush() during IBSS disconnect, and add synchronize_net() if flushing didn't, so that the synchronize_net() always happens between turning the carrier off and telling the driver, avoiding this race.
Which versions are affected by CVE-2026-93804?
How do I fix CVE-2026-93804?
Apply the vendor's patch.
Is CVE-2026-93804 being exploited?
There is no known exploitation of CVE-2026-93804 in the wild and no public exploit code.
Sources
Also known as AZL-103841, BELL-CVE-2026-93804, DEBIAN-CVE-2026-93804, GHSA-f3pr-77p4-f6r5, UBUNTU-CVE-2026-93804.