Source: psirt@nvidia.com
NVIDIA Trusted OS contains a vulnerability in an SMC call handler, where failure to validate untrusted input may allow a highly privileged local attacker to cause information disclosure and compromise integrity. The scope of the impact can extend to other components.
NVIDIA Trusted OS (TeOS) is vulnerable to a critical flaw allowing a local attacker with high privileges to disclose sensitive information and compromise system integrity. The vulnerability stems from insufficient input validation within an SMC (Secure Monitor Call) handler, potentially enabling attackers to escalate privileges and gain control over other system components. This could lead to a complete system compromise.
Step 1: Privilege Escalation: The attacker must already have a level of local access, potentially user-level privileges, within the system. This could be achieved through other vulnerabilities or social engineering.
Step 2: Payload Crafting: The attacker crafts a malicious payload designed to exploit the SMC call handler's input validation flaw. This payload is specifically tailored to trigger the vulnerability.
Step 3: SMC Call Initiation: The attacker initiates an SMC call, passing the crafted payload as input to the vulnerable handler.
Step 4: Handler Execution: The SMC handler, due to the lack of input validation, processes the malicious payload. This could lead to information disclosure, memory corruption, or other unintended consequences.
Step 5: Information Disclosure/Integrity Compromise: The vulnerability allows the attacker to read sensitive data, such as cryptographic keys or system configuration details, or to modify critical system components, leading to a compromise of system integrity and potentially complete system control.
The vulnerability lies within the NVIDIA Trusted OS's SMC call handler. The root cause is a failure to properly validate untrusted input provided to the SMC handler. This lack of validation allows an attacker to craft malicious input that, when processed by the handler, leads to information disclosure and/or integrity violations. The specific flaw likely involves a missing or inadequate check on the size, format, or content of the input data. This could manifest as a buffer overflow, an integer overflow, or other memory corruption vulnerabilities. The impact is amplified because the SMC handler operates with elevated privileges within the trusted execution environment (TEE), granting the attacker significant control over the system's security and other components.
Due to the nature of the vulnerability, it's a high-value target for sophisticated threat actors. APT groups with a focus on hardware and firmware exploitation, such as those known to target NVIDIA hardware, are likely to be interested. The vulnerability could be incorporated into existing exploit kits or used in targeted attacks. No specific APT groups are definitively linked to exploitation at this time. CISA KEV status: Not Listed
Monitor system logs for unusual SMC call patterns or suspicious activity related to TeOS. Analyze logs for error messages or unexpected behavior from the SMC handler.
Implement intrusion detection systems (IDS) to identify anomalous network traffic or system behavior that could indicate exploitation attempts.
Monitor for changes to critical system files or configurations that could be indicative of a successful exploit.
Analyze memory dumps and system state information for signs of memory corruption or unauthorized code execution within the TeOS environment.
Use hardware-based security features, such as Intel SGX or AMD SEV, to monitor the integrity of the TeOS environment.
Apply the latest NVIDIA security updates and patches to the affected products. These patches should address the input validation flaws in the SMC call handler.
Implement a defense-in-depth strategy, including strong access controls, least privilege principles, and regular security audits.
Review and harden the system's configuration to minimize the attack surface. Disable unnecessary services and features.
Monitor system logs and network traffic for suspicious activity. Implement robust logging and alerting mechanisms.
Consider using hardware-based security features, such as Intel SGX or AMD SEV, to enhance the security of the TeOS environment.