SB20261022165 - Out-of-bounds write in Linux kernel core



SB20261022165 - Out-of-bounds write in Linux kernel core

Published: October 22, 2026

Security Bulletin ID SB20261022165
CSH Severity
Low
Patch available
YES
Number of vulnerabilities 1
Exploitation vector Local access
Highest impact Data manipulation

Breakdown by Severity

Low 100%
  • Low
  • Medium
  • High
  • Critical

Description

This security bulletin contains information about 1 vulnerability.


1) Out-of-bounds write (CVE-ID: CVE-2026-98588)

CWE-ID: CWE-787 - Out-of-bounds write

CVSSv4: 6.8 [CVSS:4.0/AV:L/AC:L/AT:N/PR:H/UI:N/VC:N/VI:H/VA:H/SC:N/SI:N/SA:N]


The vulnerability allows a local privileged user to corrupt kernel memory or cause a denial of service.

The vulnerability exists due to an out-of-bounds write in sock_map_free() when freeing a SOCKMAP whose entry count exceeds the range of its signed integer iterator. A local privileged user can create and destroy a SOCKMAP with max_entries = 0xffffffff to trigger signed integer overflow and write outside the socket array, corrupting an unrelated allocation or crashing the kernel.

Exploitation requires the 32 GiB allocation to succeed on a large-memory host.


Remediation

Install update from vendor's website.