SB20261007117 - Out-of-bounds read in Linux kernel ipv6



SB20261007117 - Out-of-bounds read in Linux kernel ipv6

Published: October 7, 2026

Security Bulletin ID SB20261007117
CSH Severity
Low
Patch available
YES
Number of vulnerabilities 1
Exploitation vector Remote access
Highest impact Information disclosure

Breakdown by Severity

Low 100%
  • Low
  • Medium
  • High
  • Critical

Description

This security bulletin contains information about 1 vulnerability.


1) Out-of-bounds read (CVE-ID: CVE-2026-98241)

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

CVSSv4: 0 [CVSS:4.0/AV:N/AC:L/AT:P/PR:N/UI:N/VC:N/VI:N/VA:N/SC:N/SI:N/SA:N]


The vulnerability allows a remote attacker to trigger out-of-bounds reads in kernel memory.

The vulnerability exists due to out-of-bounds reads caused by treating request sockets as full IPv6 sockets in xfrm6_local_rxpmtu() and xfrm6_local_error() when accessing inet_sock or ipv6_pinfo state through skb->sk. A remote attacker can trigger local PMTU or error handling for TCP SYN-ACK packets owned by a request socket to trigger out-of-bounds reads in kernel memory.

The vulnerable path is reachable when rerouting selects an IPv6 XFRM tunnel route with a lower MTU while a TCP_NEW_SYN_RECV request socket remains attached to the packet.


Remediation

Install update from vendor's website.