Introduction
Privilege escalation through firmware vulnerabilities can undermine hardware security boundaries and persist across OS reinstalls. CVE-2025-20037 is a time-of-check time-of-use (TOCTOU) race condition in Intel's Converged Security and Management Engine (CSME) firmware, affecting a wide range of Intel-based systems in enterprise and consumer environments.
Intel is the dominant provider of x86 processors and chipsets worldwide. Its CSME is embedded in millions of PCs and servers, providing critical security and remote management features. Vulnerabilities in this component have industry-wide impact due to the ubiquity of Intel hardware.
Technical Information
CVE-2025-20037 is classified as a time-of-check time-of-use (TOCTOU) race condition (CWE-367) within the firmware of some Intel CSME implementations. The vulnerability occurs when the firmware performs a security check or validates a resource, but the actual use of that resource happens later. If an attacker with privileged local access can change the state of the resource in the interval between check and use, they may be able to escalate privileges or bypass security controls.
This flaw is exploitable only by a local user with elevated privileges and requires precise timing to win the race condition. The CSME operates with broad system privileges, so a successful exploit could allow deeper compromise of system security boundaries. No public code snippets or detailed vulnerable code locations are available for this issue.
Affected Systems and Versions
- Intel Converged Security and Management Engine (CSME) firmware prior to version 16.1.38.2676
- Intel Converged Security and Management Engine (CSME) firmware prior to version 14.1.77.2497
- Affects systems using these firmware versions, including a wide range of Intel-based desktops, laptops, and servers
Vendor Security History
Intel has a documented history of firmware vulnerabilities in its management engines, including:
- Previous TOCTOU race conditions (e.g., CVE-2024-22185 in Intel ACTM)
- Multiple privilege escalation issues in Intel ME, AMT, and related firmware (see INTEL-SA-01152, INTEL-SA-01203)
- Coordinated disclosure and patching is standard, but recurring issues highlight the complexity of securing low-level firmware