SB2026040649 - NULL pointer dereference in Linux kernel mac80211
Published: April 6, 2026
Security Bulletin ID
SB2026040649
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) NULL pointer dereference (CVE-ID: CVE-2026-31394)
The vulnerability allows a local attacker to cause a denial of service.
The vulnerability exists due to a NULL pointer dereference in ieee80211_chan_bw_change for AP_VLAN stations when processing channel bandwidth changes during CSA. A local attacker can trigger the vulnerable code path to cause a denial of service.
The issue affects stations on AP_VLAN interfaces such as 4addr WDS clients, where link reservation data can remain zero-initialized with a NULL channel pointer.
Remediation
Install update from vendor's website.