CVE-2022-26360 : What You Need to Know
Understand CVE-2022-26360, a Xen vulnerability allowing memory corruption in PCI devices. Learn about impact, affected systems, and mitigation steps.
This article provides detailed information about CVE-2022-26360, a vulnerability related to IOMMU: RMRR (VT-d) and unity map (AMD-Vi) handling issues in Xen.
Understanding CVE-2022-26360
This CVE relates to certain PCI devices in a system that might be assigned Reserved Memory Regions (RMRR) for Intel VT-d or Unity Mapping ranges for AMD-Vi, leading to potential memory corruption and unpredictable behavior.
What is CVE-2022-26360?
The issue arises from the violation of requirements for continuous accessibility of memory regions by active devices, causing unpredictable behavior, including Denial of Service (DoS) affecting the entire host.
The Impact of CVE-2022-26360
The precise impact varies but could result in a Denial of Service affecting the entire host, with potential for privilege escalation and information leaks.
Technical Details of CVE-2022-26360
This section delves into the vulnerability description, affected systems, versions, and exploitation mechanism.
Vulnerability Description
PCI devices in a system assigned RMRR or unity map ranges may experience memory corruption and unpredictable behavior due to violated requirements for continuous memory region accessibility.
Affected Systems and Versions
All Xen versions supporting PCI passthrough are affected. Only x86 systems with IOMMU hardware are vulnerable.
Exploitation Mechanism
The vulnerability can be exploited in x86 guests with physical devices passed through to them, particularly those with associated RMRR or unity maps.
Mitigation and Prevention
Learn about immediate steps to take and long-term security practices to prevent exploitation.
Immediate Steps to Take
Avoid passing physical devices with associated RMRRs or unity maps to untrusted guests to prevent the vulnerability.
Long-Term Security Practices
Implement strict device assignment policies and regularly monitor and update RMRR or unity map associations.
Patching and Updates
Stay informed about security advisories and promptly apply patches released by Xen.