CVE-2026-31637
Full vulnerability record from the local CVENow database.
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.
Severity
CRITICAL
CVSS score
9.8
(v3.1)
Vulnerability status
Modified
Source identifier
416baaa9-dc9f-4396-8d5f-8c081fb06d67
Published
2026-04-24 15:16:43.020000
Last modified
2026-10-19 19:18:02.423000
View original CVE JSON
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"sourceIdentifier": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
"published": "2026-04-24T15:16:43.020",
"lastModified": "2026-10-19T19:18:02.423",
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"value": "In the Linux kernel, the following vulnerability has been resolved:\n\nrxrpc: reject undecryptable rxkad response tickets\n\nrxkad_decrypt_ticket() decrypts the RXKAD response ticket and then\nparses the buffer as plaintext without checking whether\ncrypto_skcipher_decrypt() succeeded.\n\nA malformed RESPONSE can therefore use a non-block-aligned ticket\nlength, make the decrypt operation fail, and still drive the ticket\nparser with attacker-controlled bytes.\n\nCheck the decrypt result and abort the connection with RXKADBADTICKET\nwhen ticket decryption fails."
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