CVE-2023-53551 usb: gadget: u_serial: Add null pointer check in gserial_resume

Medium 5.5 Published Updated

A null pointer dereference in the Linux kernel USB gadget serial driver can cause a system crash when a wakeup interrupt occurs after disconnection.

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-2023-53551?

CVE-2023-53551 is a medium-severity vulnerability in Linux kernel, published on 4 Oct 2025. 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:

usb: gadget: u_serial: Add null pointer check in gserial_resume

Consider a case where gserial_disconnect has already cleared gser->ioport. And if a wakeup interrupt triggers afterwards, gserial_resume gets called, which will lead to accessing of gser->ioport and thus causing null pointer dereference.Add a null pointer check to prevent this.

Added a static spinlock to prevent gser->ioport from becoming null after the newly added check.

Weakness: CWE-476

Which versions are affected by CVE-2023-53551?

It affects 1 product.

Products include Linux kernel.

How do I fix CVE-2023-53551?

Apply the vendor's patch.

Is CVE-2023-53551 being exploited?

There is no known exploitation of CVE-2023-53551 in the wild and no public exploit code.

All Linux kernel vulnerabilities

Sources

Also known as BELL-CVE-2023-53551, DEBIAN-CVE-2023-53551, GHSA-x2mg-85cj-xc8q, UBUNTU-CVE-2023-53551.

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