CVE-2020-12928: AMD Ryzen Master Privilege Escalation Flaw

CVE-2020-12928 Overview

A privilege escalation vulnerability exists in a dynamically loaded AMD driver in AMD Ryzen Master V15. This flaw allows any authenticated user on the local system to escalate their privileges to NT AUTHORITY\SYSTEM, the highest privilege level on Windows operating systems. The vulnerability stems from improper exposure of dangerous methods or functions in the driver component.

Critical Impact

Any authenticated local user can gain complete SYSTEM-level access to the affected Windows machine, potentially leading to full system compromise, data theft, and persistent malware installation.

Affected Products

• AMD Ryzen Master (all versions prior to patched release)

Discovery Timeline

• October 13, 2020 - CVE CVE-2020-12928 published to NVD
• November 21, 2024 - Last updated in NVD database

Technical Details for CVE-2020-12928

Vulnerability Analysis

This vulnerability is classified under CWE-749 (Exposed Dangerous Method or Function), indicating that the AMD Ryzen Master driver exposes functionality that can be leveraged by low-privileged users to perform privileged operations. AMD Ryzen Master is a utility designed to provide overclocking and system monitoring capabilities for AMD Ryzen processors. The driver component that facilitates communication between the user-mode application and hardware operates at kernel level with SYSTEM privileges.

The flaw exists in how the dynamically loaded driver handles requests from authenticated users. Due to insufficient validation of the caller's privilege level or improper access controls on the exposed driver interfaces, any authenticated user can invoke dangerous driver methods that execute with elevated privileges.

Root Cause

The root cause of this vulnerability lies in the exposed dangerous method or function (CWE-749) within the AMD Ryzen Master driver. The driver fails to properly validate or restrict access to privileged operations, allowing authenticated users with low privileges to invoke kernel-level functionality. This design flaw enables local privilege escalation by permitting unprivileged processes to communicate with the driver and trigger actions that execute with SYSTEM-level authority.

Attack Vector

This is a local attack vector vulnerability requiring the attacker to have authenticated access to the target system. The exploitation sequence involves:

1. An attacker with low-privilege access (standard user account) on a Windows system with AMD Ryzen Master V15 installed identifies the vulnerable driver
2. The attacker crafts a malicious request to the driver through its exposed interface (typically via IOCTL calls)
3. The driver processes the request without adequately verifying the caller's privileges
4. The requested operation executes with SYSTEM-level privileges, allowing the attacker to perform actions such as executing arbitrary code, modifying system files, or creating new administrator accounts

The vulnerability requires no user interaction once the attacker has local access, making it particularly dangerous in multi-user environments or when combined with other attack vectors that provide initial access.

Detection Methods for CVE-2020-12928

Indicators of Compromise

• Unusual IOCTL communications with AMD Ryzen Master driver components
• Unexpected processes running with SYSTEM privileges spawned by non-administrative users
• New user accounts or privilege changes initiated outside normal administrative workflows
• Suspicious driver loading activity associated with AMD Ryzen Master components

Detection Strategies

• Monitor for anomalous driver interactions using endpoint detection and response (EDR) solutions
• Implement application whitelisting to detect unauthorized binaries attempting to communicate with the vulnerable driver
• Enable Windows Security Event logging for privilege escalation events (Event IDs 4672, 4673, 4674)
• Deploy behavioral analysis to detect privilege escalation patterns from low-privileged user sessions

Monitoring Recommendations

• Configure SentinelOne agents to monitor for suspicious driver communications and privilege escalation attempts
• Enable audit logging for process creation events to track unusual SYSTEM-level process spawning
• Monitor file system changes to critical system directories that could indicate post-exploitation activity
• Implement network segmentation monitoring to detect lateral movement following potential privilege escalation

How to Mitigate CVE-2020-12928

Immediate Actions Required

• Update AMD Ryzen Master to the latest patched version immediately
• Audit systems for the presence of AMD Ryzen Master V15 and prioritize remediation
• Consider temporarily uninstalling AMD Ryzen Master on systems where it is not critical until patching is complete
• Implement the principle of least privilege to minimize the number of authenticated users on affected systems

Patch Information

AMD has released security updates to address this vulnerability. Users should consult the AMD Product Security page for the latest security patches and update instructions. Ensure that AMD Ryzen Master is updated to a version released after the security advisory addressing CVE-2020-12928.

Workarounds

• Remove AMD Ryzen Master from systems where overclocking functionality is not required
• Restrict local logon access to trusted users only on systems with AMD Ryzen Master installed
• Implement application control policies to prevent unauthorized applications from interacting with the driver
• Use network-level authentication and strong access controls to limit who can authenticate to affected systems

# Check for installed AMD Ryzen Master version
wmic product where "name like '%AMD Ryzen Master%'" get name,version

# If removal is preferred as a workaround, uninstall via command line
wmic product where "name like '%AMD Ryzen Master%'" call uninstall /nointeractive