In the Linux kernel, the following vulnerability has been resolved: rxrpc: reject undecryptable...

CVE-2026-31637 → View on GitHub ↗ View on CVE.org ↗ View on NVD ↗

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.

Basic information

Type
unreviewed
Severity
critical
Advisory on GitHub
Open advisory ↗
Repository advisory
—
Source code
Not specified
Published (advisory)
2026-04-24 15:32:36 UTC
Updated
2026-06-01 18:31:29 UTC
NVD published
2026-04-24

EPSS Score

Score Percentile
0.10% 26.61%

CVSS Scores

Base score Version Severity Vector
9.8 3.1 —
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H Click to expand
Attack vector (AV:N)
Could be attacked over the internet or any normal routed network—not just someone sitting at the machine.
Attack complexity (AC:L)
Once they can reach the bug, pulling it off is straightforward—no weird race conditions or rare setup.
Privileges required (PR:N)
No account or special rights needed—anonymous or random user is enough.
User interaction (UI:N)
Nobody has to click “OK” or open a trap file; it can work without a victim helping.
Scope (S:U)
Damage stays in the same “trust bubble” as the broken component—no big spill into unrelated systems.
Confidentiality (C:H)
Serious risk that confidential data gets exposed in a big way.
Integrity (I:H)
They could widely tamper with or forge data—trust in the data is badly hurt.
Availability (A:H)
Could take the service down hard or make it unusable for people who depend on it.

Identifiers

Type Value
GHSA GHSA-45qq-4p94-jp2v ↗
CVE CVE-2026-31637 ↗

References

cvelogic Threat Intelligence