CVE-2021-3609

A flaw was found in the CAN BCM networking protocol in the Linux kernel, where a local attacker can abuse a flaw in the CAN subsystem to corrupt memory, crash the system or escalate privileges.

Red Hat Product Security is aware of this issue. Updates will be released as they become available.

For Red Hat Virtualization, this flaw is rated Moderate as CAN is not used on host nodes.

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.

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

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

The system will need to be restarted if the CAN modules are loaded. In most circumstances, the CAN kernel modules will be unable to be unloaded while any network interfaces are active and the protocol 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 or contact Red Hat Global Support Services.