SB20261022117 - Memory leak in Linux kernel ipv4



SB20261022117 - Memory leak in Linux kernel ipv4

Published: October 22, 2026

Security Bulletin ID SB20261022117
CSH Severity
Low
Patch available
YES
Number of vulnerabilities 1
Exploitation vector Local access
Highest impact Denial of service

Breakdown by Severity

Low 100%
  • Low
  • Medium
  • High
  • Critical

Description

This security bulletin contains information about 1 vulnerability.


1) Memory leak (CVE-ID: CVE-2026-98541)

CWE-ID: CWE-401 - Missing release of memory after effective lifetime

CVSSv4: 6.7 [CVSS:4.0/AV:L/AC:L/AT:N/PR:H/UI:N/VC:N/VI:N/VA:H/SC:N/SI:N/SA:N]


The vulnerability allows a local privileged user to exhaust kernel memory and cause a denial of service.

The vulnerability exists due to a failure to release packet buffers in the Linux kernel FOU receive handler when a direct encapsulation socket has a zero protocol value. A local privileged user can submit a FOU_CMD_ADD Generic Netlink request with FOU_ATTR_TYPE set to FOU_ENCAP_DIRECT while omitting FOU_ATTR_IPPROTO, then send UDP packets to the resulting socket to leak an sk_buff for each received packet and potentially exhaust kernel memory.


Remediation

Install update from vendor's website.