SB20260507283 - Improper Initialization in Linux kernel pinctrl driver

Description

This security bulletin contains information about 1 vulnerability.

1) Improper Initialization (CVE-ID: CVE-2026-43087)

CWE-ID: CWE-665 - Improper Initialization

CVSSv4: 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/E:U/U:Clear

The vulnerability allows a local user to cause a denial of service.

The vulnerability exists due to improper initialization in the mcp23s08 interrupt handling during device probe when probing a chip with interrupt-on-change enabled on some pins. A local user can trigger device initialization in this state to cause a denial of service.

The issue occurs because interrupts may be generated for pins that do not yet have a registered nested handler, leading to a kernel crash.

Remediation

Install update from vendor's website.

References

• https://git.kernel.org/stable/c/db5b8cecbdf479ad13156af750377e5b43853fab
• https://git.kernel.org/stable/c/f8c3258541a0680a4ebc08b05b2bc5fdad3288a9