SB20260727123 - Out-of-bounds read in Linux kernel tipc



SB20260727123 - Out-of-bounds read in Linux kernel tipc

Published: July 27, 2026

Security Bulletin ID SB20260727123
CSH Severity
Medium
Patch available
YES
Number of vulnerabilities 1
Exploitation vector Remote access
Highest impact Denial of service

Breakdown by Severity

Medium 100%
  • Low
  • Medium
  • High
  • Critical

Description

This security bulletin contains information about 1 vulnerability.


1) Out-of-bounds read (CVE-ID: CVE-2026-64450)

CWE-ID: CWE-125 - Out-of-bounds read

CVSSv4: CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:N/VI:N/VA:H/SC:N/SI:N/SA:N/E:U/U:Green


The vulnerability allows a remote attacker to cause a denial of service.

The vulnerability exists due to an out-of-bounds read in the TIPC broadcast Gap ACK blocks handling in tipc_bcast_sync_rcv() when processing a crafted broadcast PROTOCOL/STATE_MSG. A remote attacker can send a specially crafted broadcast STATE_MSG with a malformed Gap ACK blocks record to cause a denial of service.

Exploitation requires a TIPC neighbour that has negotiated TIPC_GAP_ACK_BLOCK.


Remediation

Install update from vendor's website.