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AMD Says Patches Coming Soon for Chip Vulnerabilities

AMD Chip Vulnerabilities to be Addressed Through BIOS Updates - No Performance Impact Expected

After investigating recent claims from a security firm that its processors are affected by more than a dozen serious vulnerabilities, chipmaker Advanced Micro Devices (AMD) on Tuesday said patches are coming to address several security flaws in its chips. 

In its first public update after the surprise disclosure of the vulnerabilities by Israeli-based security firm CTS Labs, AMD said the issues are associated with the firmware managing the embedded security control processor in some of its products (AMD Secure Processor) and the chipset used in some socket AM4 and socket TR4 desktop platforms supporting AMD processors.

Vulnerabilities found in Ryzen and other AMD processors

CTS Labs, which was unheard of until last week, came under fire shortly after its disclosure for giving AMD only a 24-hour notice before going public with its findings, and for apparently attempting to short AMD stock. The company later made some clarifications regarding the flaws and its disclosure method.

CTS Labs claimed that a number of vulnerabilities could be exploited for arbitrary code execution, bypassing security features, stealing data, helping malware become resilient against security products, and damaging hardware.

“AMD has rapidly completed its assessment and is in the process of developing and staging the deployment of mitigations,” the chipmaker wrote in an update on Tuesday. “It’s important to note that all the issues raised in the research require administrative access to the system, a type of access that effectively grants the user unrestricted access to the system and the right to delete, create or modify any of the folders or files on the computer, as well as change any settings.”

AMD said that patches will be released through BIOS updates to address the flaws, which have been dubbed MASTERKEY, RYZENFALL, FALLOUT and CHIMERA. The company said that no performance impact is expected for any of the forthcoming mitigations.

AMD attempted to downplay the risks, saying that any attacker gaining administrative access could have a wide range of attacks at their disposal “well beyond the exploits identified in this research.”

“Further, all modern operating systems and enterprise-quality hypervisors today have many effective security controls, such as Microsoft Windows Credential Guard in the Windows environment, in place to prevent unauthorized administrative access that would need to be overcome in order to affect these security issues,” the notice continued. 

AMD also linked to a blog post from Trail of Bits, which was the first to independently review the findings from CTS. The company, which has been paid for its services, confirmed that the proof-of-concept (PoC) exploits developed by CTS Labs work as intended, but believes that there is “no immediate risk of exploitation of these vulnerabilities for most users.”

“Even if the full details were published today, attackers would need to invest significant development efforts to build attack tools that utilize these vulnerabilities. This level of effort is beyond the reach of most attackers,” Trail of Bits added.

Check Point has also confirmed two of the RYZENFALL vulnerabilities following its own review. The security firm says it does not have any relationship with CTS Labs and it has not received any payment for its services. It also noted that it does not agree with the way CTS disclosed its findings, describing it as “very irresponsible.”

Alex Ionescu, a reputable researcher and Windows security expert, also confirmed the findings and warned that “admin-level access and persistence are legitimate threats in multi-tenant IaaS and even things such as VTL0/1 (Credential Guard) when firmware and chipset trust boundaries are broken.”

“This company was previously unknown to AMD and we find it unusual for a security firm to publish its research to the press without providing a reasonable amount of time for the company to investigate and address its findings,” AMD stated last week.

Some have compared the recent AMD vulnerabilities to Meltdown and Spectre, which impact CPUs from Intel, AMD, ARM and others. However, some argued that the issues disclosed by CTS Labs are nowhere near as severe due to the fact that they mostly impact AMD’s Secure Processor technology rather than the hardware itself.

AMD did not provide specific dates that patches are expected to be released, but said it would provide additional updates on both its analysis of the issues and the related mitigation plans in the coming weeks. 

Eduard Kovacs contributed to this report

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For more than 10 years, Mike Lennon has been closely monitoring the threat landscape and analyzing trends in the National Security and enterprise cybersecurity space. In his role at SecurityWeek, he oversees the editorial direction of the publication and is the Director of several leading security industry conferences around the world.