A flaw was found in the prctl() function, where it can be used to enable indirect branch speculation after it has been disabled. This call incorrectly reports it as being ‘force disabled’ when it is not and opens the system to Spectre v2 attacks. The highest threat from this vulnerability is to confidentiality.
Red Hat has investigated whether a possible mitigation exists for this issue, and has not been able to identify a practical example. Please update as soon as possible.