CVE-2026-68125 PUBLISHED

mac802154: llsec: reject frames shorter than the authentication tag

Assigner: Linux
Reserved: 30.07.2026 Published: 10.08.2026 Updated: 10.08.2026

In the Linux kernel, the following vulnerability has been resolved:

mac802154: llsec: reject frames shorter than the authentication tag

llsec_do_decrypt_auth() computes the associated-data length for the AEAD request as

<pre>assoclen += datalen - authlen; </pre>

where datalen is the number of bytes after the MAC header and authlen (4, 8 or 16) is the length of the authentication tag. Nothing verifies that the frame actually carries at least authlen payload bytes. A secured frame whose payload is shorter than the tag makes datalen - authlen negative; assoclen is then passed to aead_request_set_ad() as an unsigned value close to 4 GiB, so crypto_aead_decrypt() walks far off the end of the scatterlist that only spans the real frame.

The frame is fully attacker-controlled and reaches this path from any IEEE 802.15.4 peer in radio range. Reject frames whose payload is shorter than the authentication tag before the subtraction.

Dynamically reproduced on a KASAN kernel as a general-protection-fault in the AEAD scatterwalk, and the fix confirmed.

Product Status

Vendor Linux
Product Linux
Versions Default: unaffected
  • affected from 4c14a2fb5d143e4ed94143be2b8c1961b47df9af to 5bbf0cd9b6a7076af86c75e87e180099be2e11ae (excl.)
  • affected from 4c14a2fb5d143e4ed94143be2b8c1961b47df9af to de80808f37d99c6dc67bb6f97eea00c8f57a8821 (excl.)
  • affected from 4c14a2fb5d143e4ed94143be2b8c1961b47df9af to f20dedce0429b293d4bad604e0d3f65d8ac96c83 (excl.)
  • affected from 4c14a2fb5d143e4ed94143be2b8c1961b47df9af to e09e0301d616c1ef38a5e64e8e4326fd39df13cc (excl.)
  • affected from 4c14a2fb5d143e4ed94143be2b8c1961b47df9af to fd3a3f28ed60c6af4b2a39933b151d6b27842c3b (excl.)
Vendor Linux
Product Linux
Versions Default: affected
  • Version 3.16 is affected
  • unaffected from 0 to 3.16 (excl.)
  • unaffected from 6.6.148 to 6.6.* (incl.)
  • unaffected from 6.12.101 to 6.12.* (incl.)
  • unaffected from 6.18.42 to 6.18.* (incl.)
  • unaffected from 7.1.6 to 7.1.* (incl.)
  • unaffected from 7.2-rc5 to * (incl.)

References