SB2026040696 - Race condition in Linux kernel shaper
Published: April 6, 2026
Security Bulletin ID
SB2026040696
Severity
Low
Patch available
YES
Number of vulnerabilities
1
Exploitation vector
Local access
Highest impact
Denial of service
Breakdown by Severity
- Low
- Medium
- High
- Critical
Description
This security bulletin contains information about 1 security vulnerability.
1) Race condition (CVE-ID: CVE-2026-23437)
The vulnerability allows a local user to cause a denial of service.
The vulnerability exists due to improper locking and missing liveness check in the net: shaper hierarchy handling when processing netlink operations that read the hierarchy under RCU. A local user can send specially crafted netlink requests to cause a denial of service.
The issue occurs because a net device reference obtained during netlink operation preparation may later be accessed under RCU without verifying that the device is still live and has not already been unregistered.
Remediation
Install update from vendor's website.