CVE-2020-29481 Explained : Impact and Mitigation

An issue was discovered in Xen through 4.14.x where access rights of Xenstore nodes are per domid, leading to potential security vulnerabilities.

Understanding CVE-2020-29481

This CVE highlights a vulnerability in Xen that could allow a newly created guest domain to inherit access rights from previously existing domains with the same domid.

What is CVE-2020-29481?

The issue arises from the fact that existing granted access rights are not removed when a domain is destroyed, potentially enabling unauthorized access to sensitive information.

The Impact of CVE-2020-29481

The vulnerability could allow a newly created guest domain to read sensitive information that belonged to a previously existing guest domain, posing a risk to data confidentiality and integrity.

Technical Details of CVE-2020-29481

This section provides more in-depth technical insights into the vulnerability.

Vulnerability Description

Xenstore nodes' access rights per domid are not properly cleared when a domain is destroyed, leading to potential unauthorized access.

Affected Systems and Versions

Xen through version 4.14.x

Exploitation Mechanism

New domains inheriting existing node permissions

Mitigation and Prevention

Protecting systems from CVE-2020-29481 requires immediate actions and long-term security practices.

Immediate Steps to Take

Apply patches provided by Xen to address the vulnerability
Monitor and restrict access to Xenstore nodes

Long-Term Security Practices

Regularly update Xen software to the latest version
Implement strong access control mechanisms to prevent unauthorized access

Patching and Updates

Stay informed about security advisories from Xen and promptly apply patches to mitigate risks