CVE-2021-28690 : What You Need to Know
Learn about CVE-2021-28690, a vulnerability in Xen systems where TSX Async Abort protections are not restored after S3 suspend, leaving CPU0 vulnerable to TAA. Find out the impact, affected versions, and mitigation steps.
A detailed overview of CVE-2021-28690 focusing on the impact, technical details, and mitigation strategies.
Understanding CVE-2021-28690
This CVE relates to the TSX Async Abort speculative security vulnerability on Xen systems.
What is CVE-2021-28690?
The vulnerability arises from TSX Async Abort protections not being restored after S3 suspend, leaving CPU0 vulnerable to TAA.
The Impact of CVE-2021-28690
This results in an information leak with significant security implications, as detailed in XSA-305.
Technical Details of CVE-2021-28690
The vulnerability affects Xen versions 4.12, 4.13.x, and 4.11.x.
Vulnerability Description
CPU0 remains susceptible to TAA after S3 suspend, posing a risk of data leakage.
Affected Systems and Versions
Xen versions 4.12, 4.13.x, and 4.11.x are affected by this vulnerability.
Exploitation Mechanism
The vulnerability occurs due to TSX Async Abort protections not being reinstated post S3 suspend.
Mitigation and Prevention
Understanding the necessary steps to protect systems from CVE-2021-28690.
Immediate Steps to Take
Disabling TSX or avoiding S3 suspend/resume can mitigate the vulnerability effectively.
Long-Term Security Practices
Regularly update Xen systems and apply security patches to prevent vulnerabilities.
Patching and Updates
Keeping Xen systems up-to-date with the latest patches and security fixes is crucial for robust security measures.