DEBIAN-CVE-2026-31696

Advisory lineage Upstream: 1 Downstream: 0
Upstream
CVE-2026-31696
Published: 01 May 2026, 14:16
Last modified:09 May 2026, 23:00

Vulnerability Summary

Overall Risk (default)
medium
31/100
CVSS Score
7.8 HIGH
3.1 (osv_debian)
EPSS Score
No data
KEV
Not listed
Ransomware
No reports
Public exploits
None found
Dark Web
Not detected

Timeline

01 May 2026, 14:16
Published
Vulnerability first disclosed
09 May 2026, 23:00
Last Modified
Vulnerability information updated

Description

In the Linux kernel, the following vulnerability has been resolved: rxrpc: Fix missing validation of ticket length in non-XDR key preparsing In rxrpc_preparse(), there are two paths for parsing key payloads: the XDR path (for large payloads) and the non-XDR path (for payloads <= 28 bytes). While the XDR path (rxrpc_preparse_xdr_rxkad()) correctly validates the ticket length against AFSTOKEN_RK_TIX_MAX, the non-XDR path fails to do so. This allows an unprivileged user to provide a very large ticket length. When this key is later read via rxrpc_read(), the total token size (toksize) calculation results in a value that exceeds AFSTOKEN_LENGTH_MAX, triggering a WARN_ON(). [ 2001.302904] WARNING: CPU: 2 PID: 2108 at net/rxrpc/key.c:778 rxrpc_read+0x109/0x5c0 [rxrpc] Fix this by adding a check in the non-XDR parsing path of rxrpc_preparse() to ensure the ticket length does not exceed AFSTOKEN_RK_TIX_MAX, bringing it into parity with the XDR parsing logic.

CVSS Metrics

  • v3.1•HIGH•Score: 7.8CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H

Affected Systems

  • debian•linux

    all | all | all | < 6.12.85-1 | < 7.0.3-1

References (1)