CVE-2026-98698 wifi: mac80211: handle empty FILS association request payload
A remote attacker can cause a kernel crash or memory corruption by sending a crafted FILS association request with an empty payload to a Linux Wi-Fi interface.
- 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-2026-98698?
CVE-2026-98698 is a vulnerability in Linux, published on 18 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: handle empty FILS association request payload
fils_encrypt_assoc_req() accepts a (Re)Association Request frame whose last element is the FILS Session element. crypt_len is then zero and aes_siv_encrypt() is called with an empty plaintext.
kmemdup() returns ZERO_SIZE_PTR for a zero-length allocation, so the unconditional sg_init_one() puts an invalid page into the scatterlist. With CONFIG_DEBUG_SG this triggers a kernel BUG in sg_set_buf(); without the debug check the bogus page is handed to the crypto backend.
AES-SIV is defined for empty plaintext and the S2V result is then the complete output, so handle this case before the CTR step, which has nothing to encrypt.
Which versions are affected by CVE-2026-98698?
How do I fix CVE-2026-98698?
Apply the vendor's patch.
Is CVE-2026-98698 being exploited?
There is no known exploitation of CVE-2026-98698 in the wild and no public exploit code.
Sources
Also known as AZL-108744, BELL-CVE-2026-98698, DEBIAN-CVE-2026-98698, GHSA-873v-4wm2-m9cr, UBUNTU-CVE-2026-98698.