CVE-2026-98184 wifi: mwifiex: prevent authentication frame length truncation

Not scored Published 6 Oct 2026 Updated 19 Oct 2026

A local attacker with CAP_NET_ADMIN can trigger a heap buffer overflow in the mwifiex Wi-Fi driver via integer truncation, potentially leading to code execution or privilege escalation.

Exploited in the wild: Not known
Login needed: An administrator
Attackable: Local or same network only
Victim action needed: Not needed
Fix: Available

What is CVE-2026-98184?

CVE-2026-98184 is a 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: mwifiex: prevent authentication frame length truncation

mwifiex_cfg80211_authenticate() derives the authentication frame length from req->ie_len and req->auth_data_len, both of type size_t, but stores it in a u16.

NL80211_ATTR_AUTH_DATA only has a minimum length policy. Since nla_len is a u16, a single attribute can carry up to 65531 bytes of payload, so the sum can exceed U16_MAX before it is assigned to pkt_len. The truncated pkt_len determines the skb frame area, while the copy length remains req->auth_data_len - 4, resulting in a heap buffer overflow.

For example, with auth_data_len equal to 65510 and no IEs, the sum is 65546. It is truncated to 10 and then reduced by four to 6. The driver appends only six bytes to the skb with skb_put(), but then copies 65506 user-provided bytes into the authentication body.

Reaching this path requires CAP_NET_ADMIN in the user namespace owning the network namespace, an up station netdev, and a suitable BSS/SAE authentication request.

Compute the length in size_t, reject values that cannot be represented by the firmware's u16 frame length field, and only then assign it to pkt_len.

Which versions are affected by CVE-2026-98184?

How do I fix CVE-2026-98184?

Apply the vendor's patch.

Is CVE-2026-98184 being exploited?

There is no known exploitation of CVE-2026-98184 in the wild and no public exploit code.

Sources

Also known as BELL-CVE-2026-98184, DEBIAN-CVE-2026-98184, GHSA-m63w-cm3m-w2gf, UBUNTU-CVE-2026-98184.