wifi: mac80211: handle empty FILS association request payload

Summary

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.

Timeline

1. Oct 18, 2026, 3:46 PM UTCCVE published
2. Oct 21, 2026, 12:55 PM UTCRecord last updated

Affected versions

• Linux Linux

  From 39404feee691a2dc524a629ed6eb5cfe5d8898d1 · fixed in 0b1e4a7eeb6a301ee33bd318982927cbdbae9f36; From 39404feee691a2dc524a629ed6eb5cfe5d8898d1 · fixed in 2f5b62f6534d336a62fdb9e88b186dd70b4323ef; From 39404feee691a2dc524a629ed6eb5cfe5d8898d1 · fixed in 452f1c9b76f7a122bbc4630b9691bda4809677c4; From 39404feee691a2dc524a629ed6eb5cfe5d8898d1 · fixed in 20f939b0c151d1d28e6b62a76b2454fa6fe877f2; From 39404feee691a2dc524a629ed6eb5cfe5d8898d1 · fixed in 5bfd4b0b40b79781d900cb2f7da0685070f53c67

• Linux Linux

  4.10

• KernelLinux

  From 4.10.0 · fixed in 6.6.160; From 6.7.0 · fixed in 6.12.113; From 6.13.0 · fixed in 6.18.56; From 6.19.0 · fixed in 7.2.10

References 5