CVE-2020-10766
kernel: Rogue cross-process SSBD shutdown. Linux scheduler logical bug allows an attacker to turn off the SSBD protection.
Severity
ImportantRed Hat Product Security
CVSS 3.1
Review impact separately from score.
Published · June 10, 2020
Updated · June 28, 2026
Description
A logic bug flaw was found in the Linux kernel’s implementation of SSBD. A bug in the logic handling allows an attacker with a local account to disable SSBD protection during a context switch when additional speculative execution mitigations are in place. This issue was introduced when the per task/process conditional STIPB switching was added on top of the existing SSBD switching. The highest threat from this vulnerability is to confidentiality.
Statement
This flaw is rated as having Important impact because it can be used to disable Spectre v4, 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