SB20260626221 - Use-after-free in Linux kernel netfilter



SB20260626221 - Use-after-free in Linux kernel netfilter

Published: June 26, 2026

Security Bulletin ID SB20260626221
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) Use-after-free (CVE-ID: CVE-2026-52912)

CWE-ID: CWE-416 - Use After Free

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 a use-after-free in nf_queue when reinjecting queued bridge LOCAL_IN packets. A remote attacker can trigger packet queueing and later reinjection to cause a denial of service.

The issue occurs because skb->dev can still reference a freed bridge master device while the packet remains queued.


Remediation

Install update from vendor's website.