NULL pointer dereference in Linux kernel - CVE-2026-74738
Published: August 27, 2026
Vulnerability identifier: #VU145990
CSH Severity: Low
CVSS v4: 6.8 [CVSS:4.0/AV:L/AC:L/AT:N/PR:L/UI:N/VC:N/VI:N/VA:H/SC:N/SI:N/SA:N]
CVE-ID: CVE-2026-74738
CWE-ID: CWE-476
Exploitation vector: Local access
Exploit availability:
No public exploit available
Vulnerability details
The vulnerability allows a local attacker to cause a denial of service.
The vulnerability exists due to a NULL function pointer dereference in regmap_sdw_mbq_poll_busy() in the regmap sdw-mbq component when handling devices that answer COMMAND_IGNORED and no readable_reg callback is set. A local attacker can trigger the code path to cause a denial of service.
The issue occurs because a missing readable_reg callback is treated incorrectly during Function Busy polling after an -ENODATA condition.
Affected software
Linux kernel
How to mitigate CVE-2026-74738
Install security update from vendor's repository.
Linux kernel - update to 7.0 rc3