SB20260824166 - Use-after-free in Linux kernel tty serial driver

Description

This security bulletin contains information about 1 vulnerability.

1) Use-after-free (CVE-ID: CVE-2026-74652)

CWE-ID: CWE-416 - Use After Free

CVSSv4: 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]

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

The vulnerability exists due to a use-after-free in the RS485 hrtimer handling in the amba-pl011 serial driver when removing or shutting down a device while timer callbacks can still be armed from the IRQ handler. A local user can trigger device shutdown or removal during RS485 activity to cause a denial of service.

The issue affects the suspend-then-unbind path, where shutdown is not called.

Remediation

Install update from vendor's website.

References

• https://git.kernel.org/stable/c/36672c8d7d14e9c43287528455d2c97b526ea6ad
• https://git.kernel.org/stable/c/759ead98a39fb625be302f9aa66290985dcaa325
• https://git.kernel.org/stable/c/e57f0aa5c35be37218ba0e4887b241584dd4b2d2