A flaw was found in the Linux kernel’s implementation for ADU devices from Ontrak Control Systems, where an attacker with administrative privileges and access to a local account could pre-groom the memory and physically disconnect or unload a module. The attacker must be able to access either of these two events to trigger the use-after-free, and then race the access to the use-after-free, to create a situation where key USB structs can be manipulated into corrupting memory.

Mitigation

As the system module will be auto-loaded when a device that uses the driver is attached (via USB), its use can be disabled by preventing the module from loading with the following instructions:

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

The system will need to be restarted if the adutux module are loaded. In most circumstances, the kernel modules will be unable to be unloaded while any 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.