CVE-2026-90375 wifi: mt76: fix non-AQL packet accounting for MLO stations
A logic error in the mt76 Wi-Fi driver causes incorrect packet accounting, leading to permanent TX scheduler refusal and denial of service for MLO stations.
- 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-2026-90375?
CVE-2026-90375 is a denial of service vulnerability in Linux, published on 17 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: mt76: fix non-AQL packet accounting for MLO stations
__mt76_tx_queue_skb() overrides the wcid passed by the driver with sta->drv_priv, so the wcid might incorrectly be changed after TX, causing wcid->non_aql_packets to be counted on the wrong wcid. For example, on the AP side, if a station's setup link is the 5G link and the station uses 2G to transmit a frame, the value of non_aql_packets is increased on the 5G wcid but decreased on the 2G wcid. Once the inflated counter exceeds MT_MAX_NON_AQL_PKT, the TX scheduler permanently refuses to service the station.
Drop the reassignment and account on the wcid used for transmission. This also records the actual wcid in the queue entry.
Which versions are affected by CVE-2026-90375?
How do I fix CVE-2026-90375?
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-2026-90375 being exploited?
There is no known exploitation of CVE-2026-90375 in the wild and no public exploit code.
Sources
Also known as AZL-102755, BELL-CVE-2026-90375, DEBIAN-CVE-2026-90375, GHSA-c2f5-4c4q-2g8j, UBUNTU-CVE-2026-90375.