CVE-2026-68326 wifi: mwifiex: bound uAP association event IEs to the event buffer
A malicious Wi-Fi device can trigger a slab-out-of-bounds read in the mwifiex driver, potentially leaking kernel memory to an attacker.
- 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-2026-68326?
CVE-2026-68326 is a high-severity vulnerability in Linux, published on 10 Aug 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: mwifiex: bound uAP association event IEs to the event buffer
mwifiex_process_uap_event() handles EVENT_UAP_STA_ASSOC by exposing the (re)association request IEs that the firmware copies into the event:
sinfo->assoc_req_ies = &event->data[len]; len = (u8 *)sinfo->assoc_req_ies - (u8 *)&event->frame_control; sinfo->assoc_req_ies_len = le16_to_cpu(event->len) - (u16)len;
event->len is supplied by the device firmware and is never validated, and the subtraction is unchecked. assoc_req_ies points into adapter->event_body[MAX_EVENT_SIZE], a fixed-size array embedded in the kmalloc()'d struct mwifiex_adapter.
On the ap_11n_enabled path mwifiex_set_sta_ht_cap() walks these IEs with cfg80211_find_ie(), whose for_each_element() loop dereferences each element header. A firmware-reported event->len larger than the bytes actually received makes assoc_req_ies_len describe IEs that extend past event_body, so the walk reads out of the adapter slab object, a slab-out-of-bounds read (KASAN: slab-out-of-bounds in cfg80211_find_ie). An event->len smaller than the header instead makes the int subtraction negative, which wraps to a huge size_t when stored in assoc_req_ies_len. The same length is handed to cfg80211_new_sta(), so a more modest over-claim can also copy stale event_body bytes into the NL80211_CMD_NEW_STATION notification.
A malicious or malfunctioning mwifiex device (USB/SDIO/PCIe) can deliver such an event while the interface is in AP/uAP mode.
Validate event->len before use: reject a length that underflows the header or that would place the IEs outside the event_body[] buffer the event was copied into. event->len here is struct mwifiex_assoc_event.len, a payload field internal to this event, not the transport frame length, so it is validated in this handler rather than at the generic MWIFIEX_TYPE_EVENT receive path, which only sees the event cause and the transport frame length. The bound is against event_body[MAX_EVENT_SIZE] rather than the actually-received length because the transports store the event differently (USB and SDIO leave the 4-byte event header in event_skb, PCIe strips it via skb_pull), whereas event_body is the single fixed buffer all of them copy the event into. This is the event-path analogue of the receive-path bounds checks added in commit 119585281617 ("wifi: mwifiex: Fix OOB and integer underflow when rx packets").
Weakness: CWE-125
Which versions are affected by CVE-2026-68326?
How do I fix CVE-2026-68326?
Apply the vendor's patch.
Is CVE-2026-68326 being exploited?
There is no known exploitation of CVE-2026-68326 in the wild and no public exploit code.
Sources
Also known as BELL-CVE-2026-68326, DEBIAN-CVE-2026-68326, GHSA-2q54-jxw8-pqqr, UBUNTU-CVE-2026-68326.