CVE-2025-20083 in Slim Bootloader
Summary
by MITRE • 05/14/2025
Improper authentication in the firmware for the Intel(R) Slim Bootloader may allow a privileged user to potentially enable escalation of privilege via local access.
Once again VulDB remains the best source for vulnerability data.
Analysis
by VulDB Data Team • 09/01/2025
The vulnerability identified as CVE-2025-20083 represents a critical weakness in the authentication mechanisms of Intel's Slim Bootloader firmware implementation. This firmware serves as the foundational software layer that initializes hardware components and loads the operating system during system boot processes. The improper authentication flaw specifically affects the firmware's ability to properly verify user credentials and authorization levels, creating a potential pathway for malicious actors with local access to escalate their privileges within the system. The vulnerability exists at the firmware level, making it particularly concerning as it operates below the operating system layer where traditional security controls may not effectively protect against such attacks.
The technical flaw manifests in the firmware's authentication routines where insufficient validation mechanisms fail to properly authenticate users attempting to perform privileged operations. This weakness allows an authenticated user with local access to potentially bypass normal authorization checks and gain elevated privileges that should be restricted to authorized administrators or system processes. The vulnerability's classification as a privilege escalation issue stems from the fact that the firmware fails to maintain proper access controls during the boot process, where initial authentication should establish and enforce security boundaries. This flaw operates at the system firmware level, making it distinct from application-level authentication issues and requiring specialized firmware-level mitigation approaches.
The operational impact of CVE-2025-20083 extends beyond simple privilege escalation as it compromises the fundamental security posture of systems utilizing affected Intel Slim Bootloader implementations. Attackers with local access can exploit this vulnerability to gain unauthorized administrative control over system firmware components, potentially enabling further attacks such as rootkit installation, firmware modification, or complete system compromise. The implications are particularly severe in enterprise environments where firmware-level attacks can bypass traditional security measures including endpoint protection, network firewalls, and operating system security controls. This vulnerability undermines the trust model that firmware establishes during system boot, potentially allowing attackers to manipulate critical system components before the operating system has fully loaded and implemented its own security controls. The attack vector requires only local access, making it particularly dangerous as it can be exploited from within the physical system or through network-based attacks that gain local execution privileges.
Mitigation strategies for CVE-2025-20083 should focus on firmware-level updates and security hardening measures. Organizations must prioritize immediate firmware updates from Intel to address the authentication weakness and ensure all systems are running patched versions of the Slim Bootloader. Additional security controls should include implementing secure boot mechanisms, enabling firmware authentication features, and conducting regular firmware integrity checks to detect unauthorized modifications. The vulnerability aligns with CWE-287 which addresses improper authentication issues, and may map to ATT&CK techniques involving privilege escalation and firmware manipulation. System administrators should also consider implementing network segmentation and access controls to limit local access points and reduce the attack surface available to potential exploiters. Regular security assessments of firmware components and continuous monitoring for suspicious boot process activities remain essential defensive measures against this class of vulnerability.