A use-after-free vulnerability was found in the Linux kernel’s cpia2_usb driver. An attacker must have physical access to the system to utilize a malicious USB device to trigger the disconnect() functionality which is required to trigger this flaw. A local account is also required to take advantage of the use-after-free memory condition. System availability is the highest threat from this vulnerability.

Mitigation

As the cpia2 module will be auto-loaded when required, its use can be disabled by preventing the module from loading with the following instructions:

echo "install cpia2 /bin/true" >> /etc/modprobe.d/disable-cpia2.conf

The system will need to be restarted if the cpia2 modules are loaded. In most circumstances, the cpia2 kernel modules will be unable to be unloaded while the hardware is in use. If the system requires this module to work correctly, this mitigation may not be suitable. If you need further assistance, see KCS article <https://access.redhat.com/solutions/41278&gt; or contact Red Hat Global Support Services.