Use-after-free in Linux kernel - CVE-2026-74652

Vulnerability identifier: #VU144888

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-2026-74652

CWE-ID: CWE-416

Exploitation vector: Local access

Exploit availability: No public exploit available

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.

Linux kernel
Ubuntu
linux (Ubuntu package)
linux-aws (Ubuntu package)
linux-gcp (Ubuntu package)
linux-oracle (Ubuntu package)
linux-ibm (Ubuntu package)
linux-hwe-7.0 (Ubuntu package)
linux-oem-7.0 (Ubuntu package)

Install security update from vendor's repository.

Linux kernel - update to 7.0 rc3
linux (Ubuntu package) - update to 7.0.0-42.42
linux-aws (Ubuntu package) - update to 7.0.0-1016.17
linux-gcp (Ubuntu package) - update to 7.0.0-1016.18
linux-oracle (Ubuntu package) - update to 7.0.0-1015.16
linux-ibm (Ubuntu package) - update to 7.0.0-1017.17
linux-hwe-7.0 (Ubuntu package) - update to 7.0.0-42.42~24.04.1
linux-oem-7.0 (Ubuntu package) - update to 7.0.0-1017.17

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

• Use-after-free in Linux kernel tty serial driver
• Ubuntu update for linux-oem-7.0
• Ubuntu update for linux, linux-aws, linux-gcp and more