CVE-2026-74652 serial: amba-pl011: cancel RS485 hrtimers after freeing IRQ
A use-after-free vulnerability in the Linux kernel's amba-pl011 serial driver allows attackers to potentially execute code or cause a denial of service via RS485 timer handling.
- Exploited in the wild
- Not known
- Login needed
- Any signed-in user
- Attackable
- Local or same network only
- Victim action needed
- Not needed
- Fix
- Available
What is CVE-2026-74652?
CVE-2026-74652 is a high-severity use after free vulnerability in Linux, published on 22 Aug 2026. It can only be exploited from the same machine or local network, with no action from the victim.
Official description
In the Linux kernel, the following vulnerability has been resolved:
serial: amba-pl011: cancel RS485 hrtimers after freeing IRQ
The RS485 trigger hrtimers are embedded in the devm-managed port and can fire after it is freed. The IRQ handler can arm a timer, so free the IRQ first and then cancel both timers.
Complete the RS485 stop without arming a timer, and cancel the timers in remove() for the suspend-then-unbind path, where shutdown is not called.
This issue was found by an in-house static analysis tool.
Which versions are affected by CVE-2026-74652?
How do I fix CVE-2026-74652?
Apply the vendor's patch.
Upgrade to the fixed version. These bugs are found with fuzzing and sanitisers and avoided by memory-safe languages. More about Use after free.
Is CVE-2026-74652 being exploited?
There is no known exploitation of CVE-2026-74652 in the wild and no public exploit code.
Sources
Also known as BELL-CVE-2026-74652, DEBIAN-CVE-2026-74652, GHSA-9x5x-pxv9-g7vg, UBUNTU-CVE-2026-74652.