CVE-2026-31637

Description

In the Linux kernel, the following vulnerability has been resolved: rxrpc: reject undecryptable rxkad response tickets rxkad_decrypt_ticket() decrypts the RXKAD response ticket and then parses the buffer as plaintext without checking whether crypto_skcipher_decrypt() succeeded. A malformed RESPONSE can therefore use a non-block-aligned ticket length, make the decrypt operation fail, and still drive the ticket parser with attacker-controlled bytes. Check the decrypt result and abort the connection with RXKADBADTICKET when ticket decryption fails.

References

• https://git.kernel.org/stable/c/22f6258e7b31dba9bf88dce4e3ee7f0f20072e60
• https://git.kernel.org/stable/c/47073aab8a3a5a7b41c9bd37d2a3dcbeeccd6c8a
• https://git.kernel.org/stable/c/58fcd1b156152613ba00a064a129fb69507ddd7d
• https://git.kernel.org/stable/c/a149dcae23309df9de1c3b6b5d468610ef5ab7de
• https://git.kernel.org/stable/c/fe4447cd95623b1cfacc15f280aab73a6d7340b2