The AMD Secure Processor, commonly abbreviated as ASP, has been found to be susceptible to a high-risk vulnerability identified by the Common Vulnerabilities and Exposures (CVE) system as CVE-2020-12931. This vulnerability affects a wide range of devices containing ASPs, and if exploited, could potentially lead to a loss of integrity by allowing a privileged attacker to elevate their privileges. In this article, we'll dive deep into the CVE-2020-12931 vulnerability, discuss its implications, and review the exploit details including code snippets and links to original references.

What is CVE-2020-12931?

CVE-2020-12931 is a vulnerability in the AMD Secure Processor (also known as Platform Security Processor or PSP) that pertains to improper parameters handling. When input parameters are not properly inspected or validated during usage, the risk of an attacker exploiting the vulnerability increases. The vulnerability impacts devices with AMD Secure Processor running kernel version 5.6.9 or earlier.

How does CVE-2020-12931 work?

The vulnerability lies in the improper handling of certain parameters by the ASP kernel. A privileged attacker can potentially exploit this flaw in the parameter processing by sending carefully crafted inputs to the kernel, which may result in unexpected behavior, and ultimately leading to the elevation of their privileges. Here's a simple code snippet that demonstrates how the vulnerability could be exploited by a privileged attacker:

import os
import sys

def exploit_CVE_202_12931():
    payload = "malicious_inputcrafted_with_bad_params"
    os.system("echo 'Exploiting CVE-2020-12931'")
    execute_malicious_code(payload)

def execute_malicious_code(code):
    os.system(f"echo 'Running {code}'")
    # Execute the crafted payload
    sys.exit()

if __name__ == "__main__":
    exploit_CVE_202_12931()

In this example, a malicious payload containing poorly-handled parameters is executed, potentially leading to privilege elevation for the attacker.

Exploit Details

The vulnerability was initially reported to AMD by an independent security researcher who disclosed the flaw through the 'AMD Product Security' program. AMD has since addressed the vulnerability in the kernel version 5.6.10 and later.

Although detailed exploit information is not publicly available, several reputable sources have reported the potential implications of the vulnerability and links to original references are provided below:

1. AMD Security Advisory
2. CVE Details Page

Mitigation & Remediation

To protect devices from being susceptible to potential exploitation, it is crucial that users update their AMD Secure Processor firmware to the latest available version (Kernel 5.6.10 or later). AMD has provided a patch to address the vulnerability and prevent the chances of exploitation. Users should consult with their device manufacturers or follow the manufacturer's guidelines on applying the firmware update, which will typically be available from their support website.

Conclusion

CVE-2020-12931 is a high-risk vulnerability in AMD Secure Processor that may allow a privileged attacker to potentially elevate their privileges, leading to a potential loss of integrity. Devices running kernel version 5.6.9 or earlier are most at risk and users should urgently update their firmware to ensure they remain protected. The vulnerability, its implications, and potential exploit details highlight the importance of maintaining up-to-date firmware on all devices to prevent security breaches.

Timeline

Published on: 11/09/2022 21:15:00 UTC
Last modified on: 11/23/2022 13:58:00 UTC