Introduction
Firmware vulnerabilities that allow privilege escalation 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. It affects a wide range of Intel-based systems in enterprise and consumer environments.
Intel is the dominant provider of x86 processors and chipsets worldwide. The CSME, embedded in millions of PCs and servers, provides critical security and remote management features. Because Intel hardware is so widespread, vulnerabilities in this component have industry-wide impact.
Technical information
CVE-2025-20037 is classified as a time-of-check time-of-use (TOCTOU) race condition (CWE-367) in the firmware of some Intel CSME implementations. The firmware performs a security check or validates a resource, then uses that resource later. If an attacker with privileged local access can change the state of the resource between the check and the use, they may be able to escalate privileges or bypass security controls.
Only a local user with elevated privileges can exploit this flaw, and winning the race takes precise timing. The CSME runs 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
Any system using these firmware versions is affected, 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 are standard, but the recurring issues show how complex low-level firmware is to secure.
