Critical severity · published Apr 24, 2026
CVE-2026-31637
rxrpc: reject undecryptable rxkad response tickets
9.8
CVSS
0.6%
EPSS
No
On KEV
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.
CVSS vector
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H
Attack vector
Network
Complexity
Low
Privileges
None
User interaction
None
Confidentiality
High
Integrity
High
Availability
High
Scope
Unchanged
Exploitation
Is it being used?
Exploit prediction (EPSS)0.6% · higher than 48% of CVEs
Exploited in the wildNo evidence yet
CISA KEVNot listed
Ransomware campaign useNot known
Affected products
Which versions
KE
Kernel · Linux
2.6.22.1 before 6.6.135; 6.7 before 6.12.82; 6.13 before 6.18.23; 6.19 before 6.19.13; 2.6.22; 7.0; +6 more · source: NVD
LI
Linux · Linux
17926a79320afa9b95df6b977b40cca6d8713cea before 252157d939d179b5d767cb860ff8fa7f8723b67a; 17926a79320afa9b95df6b977b40cca6d8713cea before a75b3b361dd481d942c5f259a82d59718a41092c; 17926a79320afa9b95df6b977b40cca6d8713cea before b3a808cd0790b5075aaa2bc3588edf02cd71d352; 17926a79320afa9b95df6b977b40cca6d8713cea before 47073aab8a3a5a7b41c9bd37d2a3dcbeeccd6c8a; 17926a79320afa9b95df6b977b40cca6d8713cea before a149dcae23309df9de1c3b6b5d468610ef5ab7de; 17926a79320afa9b95df6b977b40cca6d8713cea before 22f6258e7b31dba9bf88dce4e3ee7f0f20072e60; +3 more · source: vendor