CVE-2023-20514: AMD Secure Processor RCE Vulnerability

CVE-2023-20514 Overview

CVE-2023-20514 is a vulnerability in the AMD Secure Processor (ASP) caused by improper handling of parameters passed to functions inside the trusted execution environment (TEE). A privileged local attacker can supply an arbitrary memory value to ASP functions, leading to arbitrary code execution inside the trusted environment. The flaw is tracked under CWE-233 (improper handling of parameters) and is documented in AMD's security bulletins covering client, server, embedded, and automotive product lines.

Critical Impact
Successful exploitation grants code execution inside the AMD Secure Processor, undermining the platform's hardware root of trust and exposing confidentiality, integrity, and availability of the host and any guest workloads relying on the ASP.

Affected Products

AMD client and server processors implementing the AMD Secure Processor (ASP) — see AMD Security Bulletin SB-6024
AMD embedded processors covered by the AMD Embedded/Automotive advisory
AMD automotive processors using the ASP trusted execution environment

Discovery Timeline

2026-02-11 - CVE-2023-20514 published to NVD
2026-04-15 - Last updated in NVD database

Technical Details for CVE-2023-20514

Vulnerability Analysis

The AMD Secure Processor is an ARM-based co-processor embedded in AMD SoCs. It executes trusted firmware that handles cryptographic operations, key storage, secure boot, and the foundation for AMD SEV (Secure Encrypted Virtualization). Code that runs inside the ASP operates at a higher privilege boundary than the host x86 cores.

CVE-2023-20514 stems from improper validation of parameters passed into ASP functions from a privileged caller on the host. The trusted code accepts an attacker-controlled value and treats it as a trusted memory reference. Because the parameter is not constrained to safe ranges, the ASP dereferences or operates on memory chosen by the attacker.

The outcome is arbitrary code execution inside the trusted execution environment. An attacker who already controls a privileged context on the host can pivot across the hardware trust boundary into the ASP, where firmware-level integrity protections normally apply.

Root Cause

The root cause is missing or insufficient parameter validation in interfaces exposed by ASP firmware. Trusted code accepts caller-supplied memory values without verifying that the values reference permitted regions or structures of the expected type, classified under [CWE-233].

Attack Vector

Exploitation requires local access with high privileges on the host system. The attacker invokes the affected ASP interface and supplies a crafted memory value as a parameter. The TEE then operates on that value, allowing the attacker to redirect execution flow inside ASP firmware. No user interaction is required, and exploitation complexity is high because the attacker must already hold a privileged foothold and shape parameters to land valid execution inside the trusted firmware.

No public proof-of-concept code is referenced in AMD's advisories, and no verified exploit examples are available for this CVE.

Detection Methods for CVE-2023-20514

Indicators of Compromise

No vendor-published indicators of compromise are associated with CVE-2023-20514, as exploitation occurs below the operating system boundary and leaves limited host-visible artifacts.
Unexpected ASP firmware version mismatches between deployed and vendor-reported baseline values may indicate tampering or failed patching.

Detection Strategies

Inventory firmware versions across AMD-based fleets and compare against the fixed versions listed in AMD SB-6024 and the Embedded/Automotive bulletin.
Monitor for local privilege escalation activity that would be a prerequisite for reaching ASP interfaces, since exploitation requires high-privilege local access.
Audit kernel modules, drivers, and administrative tools that interact with the ASP mailbox or SEV interfaces for unexpected use.

Monitoring Recommendations

Centralize collection of BIOS/UEFI and AGESA update events to confirm patch deployment across servers, clients, embedded, and automotive systems.
Alert on unauthorized administrative logons, new kernel driver installations, and attempts to load unsigned code on AMD-based hosts.
Track AMD security bulletin updates for newly listed firmware revisions and re-baseline affected systems.

How to Mitigate CVE-2023-20514

Immediate Actions Required

Identify all AMD-based assets in scope, including client, server, embedded, and automotive platforms that incorporate the ASP.
Apply the firmware and AGESA updates published by AMD and the corresponding system OEMs as referenced in AMD SB-6024.
Restrict local administrative access on affected systems, since exploitation requires a high-privilege local context.

Patch Information

AMD has published fixed firmware versions in AMD Security Bulletin SB-6024 for client and server processors and in the AMD Embedded/Automotive Security Bulletin for embedded and automotive product lines. Patches are delivered through OEM BIOS/UEFI updates that bundle the corrected AGESA and ASP firmware. Coordinate with each hardware vendor to obtain the validated firmware image for the specific platform.

Workarounds

No vendor-supplied workaround replaces the firmware update; mitigations focus on reducing exposure until patching completes.
Enforce least privilege and remove unnecessary local administrator and root accounts to limit who can reach ASP interfaces.
Require signed and verified kernel drivers and disable loading of untrusted modules on AMD platforms.
For embedded and automotive deployments, follow OEM-specific guidance from the Embedded/Automotive bulletin to schedule field firmware updates.

bash

# Verify installed firmware/microcode on a Linux host before and after patching
sudo dmidecode -t bios | grep -i version
cat /proc/cpuinfo | grep -i 'microcode\|model name' | sort -u
# Compare BIOS and AGESA versions against the OEM advisory referencing AMD SB-6024