SB2026062655 - Stack-based buffer overflow in Linux kernel netfilter



SB2026062655 - Stack-based buffer overflow in Linux kernel netfilter

Published: June 26, 2026

Security Bulletin ID SB2026062655
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) Stack-based buffer overflow (CVE-ID: CVE-2026-53267)

CWE-ID: CWE-121 - Stack-based buffer overflow

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


The vulnerability allows a local user to cause memory corruption.

The vulnerability exists due to a stack-based buffer overflow in nft_ct_get_eval and nft_ct_get_fast_eval in the netfilter nft_ct subsystem when processing a crafted nftables rule that uses a template conntrack object. A local user can create a crafted rule sequence to cause memory corruption.

The issue is triggered when a conntrack template created by a preceding expression is treated as a real conntrack entry by a subsequent expression on the same skb.


Remediation

Install update from vendor's website.