CVE-2020-10768
kernel: Indirect branch speculation can be enabled after it was force-disabled by the PR_SPEC_FORCE_DISABLE prctl command.
Severity
ImportantRed Hat Product Security
CVSS 3.1
Review impact separately from score.
Published · June 9, 2020
Updated · June 28, 2026
Description
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.
Statement
This flaw is rated as having Important impact, because it enables exploitation of the previous Spectre v2 attack, which has a rating of Important.
CVSS score applicability
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.
Mitigation
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.
CVSS / CWE
CVSS 3.1 · 5.5CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:N/A:N
CWE-440 · Expected Behavior Violation