CVE-2026-43429

A flaw was found in the Linux kernel's usbtmc driver. A local user can exploit this vulnerability by providing arbitrarily long timeout values through an ioctl command. This can cause the kernel thread to hang indefinitely, leading to a Denial of Service (DoS) condition.

Moderate: A flaw in the Linux kernel's usbtmc driver allows a local attacker to cause a denial of service. By supplying an excessively long timeout value via an ioctl command, a local user can force a kernel thread to hang indefinitely, impacting system availability.

The CVSS score(s) listed for this vulnerability do not reflect the associated product's status, and are included for informational purposes to better understand the severity of this vulnerability.

To mitigate this vulnerability, prevent the usbtmc kernel module from loading if USB Test and Measurement Class devices are not in use. This can be achieved by blacklisting the module.

Create a file named /etc/modprobe.d/blacklist-usbtmc.conf with the following content:

blacklist usbtmc

After creating the file, regenerate the initramfs to ensure the blacklist is applied on boot: For RHEL 8 and 9: sudo dracut -f -v For RHEL 7: sudo dracut -f

A system reboot is required for the changes to take effect. This mitigation may impact functionality that relies on USBTMC devices.