CVE-2026-53384 serial: 8250_dw: unregister 8250 port if clk_notifier_register() fails
A use-after-free vulnerability in the Linux kernel's 8250_dw serial driver allows attackers to cause denial of service or execute code if clock registration fails.
- Exploited in the wild
- Not known
- Login needed
- Not needed
- Attackable
- Over the internet
- Victim action needed
- Not needed
- Fix
- Available
What is CVE-2026-53384?
CVE-2026-53384 is a critical use after free vulnerability in Linux kernel, published on 19 Jul 2026. An attacker can exploit it over the internet without logging in, with no action from the victim.
Official description
In the Linux kernel, the following vulnerability has been resolved:
serial: 8250_dw: unregister 8250 port if clk_notifier_register() fails
dw8250_probe() registers the 8250 port via serial8250_register_8250_port() and then, if the device has a clock, registers a clock notifier. If clk_notifier_register() fails, probe returns the error but leaves the 8250 port registered. The matching serial8250_unregister_port() lives in dw8250_remove(), which is not called when probe fails, so the port slot stays occupied until the device is rebound or the system is rebooted. The devm-allocated driver data is freed while the port still references it (via the saved private_data and serial_in/serial_out callbacks), so any access to that port slot before a rebind is a use-after-free hazard.
Unregister the port on the clk_notifier_register() error path.
Weakness: CWE-416
Which versions are affected by CVE-2026-53384?
It affects 1 product.
Products include Linux kernel.
How do I fix CVE-2026-53384?
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-2026-53384 being exploited?
There is no known exploitation of CVE-2026-53384 in the wild and no public exploit code.
Other vulnerabilities in Linux kernel
Sources
Also known as BELL-CVE-2026-53384, DEBIAN-CVE-2026-53384, GHSA-8qr8-6qvc-c8x9, ROOT-OS-DEBIAN-11-CVE-2026-53384, ROOT-OS-UBUNTU-2204-CVE-2026-53384, UBUNTU-CVE-2026-53384.