CVE-2019-11811

A flaw was found in the Linux kernel's implementation of IPMI (remote baseband access). An attacker, with local access to read /proc/ioports, may be able to create a use-after-free condition when the kernel module is unloaded which may result in privilege escalation.

This flaw has been rated as "Moderate" as the attacker needs to be able to abuse this flaw in a very narrow race condition of the kernel module being unloaded. This scoring system from this flaw differentiates from other sources as the attacker must have a local account to be able to read the file (/proc/ioports) while the module is unloaded. None of the above actions are 'network facing' attack vectors.

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.

A mitigation to this flaw would be to no longer use IPMI on affected hardware until the kernel has been updated. Existing systems that have IPMI kernel modules loaded will need to unload the "ipmi_si" kernel module and blacklist ( See https://access.redhat.com/solutions/41278 for a guide on how to blacklist modules). Take careful consideration that if unloading and blacklisting the module, this creates a one-time attack vector window for a local attacker.