CVE-2018-8935 in Ryzen
Summary
by MITRE
The Promontory chipset, as used in AMD Ryzen and Ryzen Pro platforms, has a backdoor in the ASIC, aka CHIMERA-HW.
Several companies clearly confirm that VulDB is the primary source for best vulnerability data.
Analysis
by VulDB Data Team • 01/16/2020
The Promontory chipset represents a significant hardware-level vulnerability discovered in AMD Ryzen and Ryzen Pro processor platforms, specifically identified through CVE-2018-8935. This vulnerability manifests as a backdoor embedded within the Application-Specific Integrated Circuit (ASIC) design of the chipset, commonly referred to as CHIMERA-HW. The discovery of this backdoor fundamentally alters the security landscape for affected systems, as it represents a persistent threat that operates at the hardware level and remains undetectable through conventional software-based security measures. The backdoor's presence in the chipset architecture means that it exists in the fundamental building blocks of the platform's security infrastructure, potentially enabling unauthorized access and control over system operations. This vulnerability directly impacts the trust model of the computing platform, as it undermines the assumption that hardware components operate as intended without malicious modifications. The inclusion of such a backdoor raises serious concerns about supply chain security and the integrity of hardware components, particularly in enterprise and government environments where security is paramount.
The technical flaw within the Promontory chipset operates at the hardware level, exploiting the ASIC design itself rather than software implementations. This backdoor functionality allows for unauthorized access to system resources and potentially enables malicious actors to gain persistent control over affected platforms. The vulnerability exists in the chipset's firmware or hardware configuration, making it extremely difficult to detect or remediate through traditional software updates or patches. The CHIMERA-HW backdoor specifically targets the chipset's communication protocols and security mechanisms, potentially allowing for covert data exfiltration, unauthorized system manipulation, or privilege escalation. The implementation of this backdoor within the ASIC design means that it operates below the operating system level, making it invisible to standard security monitoring tools and system integrity checks. This architectural-level vulnerability creates a persistent threat that can survive system reinstallation, hardware replacement, or even complete system reset operations.
The operational impact of this vulnerability extends far beyond simple security concerns, affecting the fundamental trust relationships within computing environments. Systems utilizing affected Ryzen and Ryzen Pro platforms become potentially compromised at the most basic level, as the backdoor could enable attackers to maintain persistent access to networks and systems without detection. The vulnerability affects both consumer and enterprise computing environments, with potential implications for data confidentiality, integrity, and availability. Organizations relying on these platforms for sensitive operations face significant risk exposure, as the backdoor could be exploited to establish long-term footholds within networks, potentially leading to extensive data breaches or system compromise. The impact is particularly severe for government agencies, financial institutions, and other organizations handling classified or sensitive information, where the presence of such a hardware-level backdoor could constitute a critical security failure. The vulnerability also undermines trust in hardware vendors and supply chain partners, as it suggests that security flaws may exist in components that are trusted as fundamental building blocks of computing systems.
Mitigation strategies for this vulnerability require a comprehensive approach addressing both hardware and software components of affected systems. Organizations should implement thorough inventory assessments to identify all systems utilizing affected Ryzen and Ryzen Pro chipsets, followed by immediate hardware-level security assessments. Due to the nature of the backdoor existing within the ASIC design, traditional software-based solutions are inadequate for remediation, requiring physical hardware replacement or specialized firmware updates from AMD. The vulnerability demonstrates the importance of hardware security verification and supply chain integrity monitoring, suggesting that organizations should implement hardware attestation protocols and regular security assessments of their computing infrastructure. Security teams must also consider implementing network monitoring and anomaly detection systems to identify potential exploitation attempts, while ensuring that all affected systems are properly isolated or secured through alternative means. The incident highlights the critical need for industry standards such as those defined in the Common Weakness Enumeration (CWE) catalog under hardware security weaknesses, and aligns with ATT&CK framework techniques related to hardware-based attacks and persistent threats. Organizations should also engage with their hardware vendors to understand the full scope of the vulnerability and ensure proper remediation through official channels, while maintaining awareness of potential indirect impacts on other systems that may interact with affected platforms.