CVE-2020-8738 in Intel
Summary
by MITRE • 11/12/2020
Improper conditions check in Intel BIOS platform sample code for some Intel(R) Processors before may allow a privileged user to potentially enable escalation of privilege via local access.
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Analysis
by VulDB Data Team • 12/06/2020
The vulnerability identified as CVE-2020-8738 resides within Intel's BIOS platform sample code for certain processors, representing a critical flaw in the privilege management mechanisms of the system firmware. This issue affects Intel processors and manifests as an improper conditions check within the BIOS implementation, creating a potential pathway for privilege escalation through local access. The vulnerability is particularly concerning because it targets the foundational firmware level where system security controls are established, making it a prime candidate for exploitation by malicious actors with local system access.
The technical flaw stems from inadequate validation of privilege conditions within the BIOS code, specifically within the platform sample implementation provided by Intel. This improper conditions check allows a privileged user to manipulate system states that should normally be restricted, potentially enabling them to elevate their privileges beyond what is intended by the system's security architecture. The vulnerability exists in the pre-processor implementation phase, meaning that systems running affected BIOS versions may be susceptible to unauthorized privilege escalation attacks. This type of flaw directly relates to CWE-284 which addresses improper access control and CWE-362 which covers concurrent execution use of a resource.
From an operational perspective, this vulnerability creates significant risks for systems running affected Intel processors, as local access by a privileged user can potentially lead to complete system compromise. The attack vector requires local access and existing user privileges, making it less likely to be exploited remotely but still dangerous in environments where local access is possible or where users have elevated privileges. The impact extends beyond simple privilege escalation to potentially allow attackers to bypass critical security controls, modify system configurations, or access sensitive data that should be protected by the system's privilege model. This vulnerability aligns with ATT&CK technique T1068 which covers 'Exploitation for Privilege Escalation' and T1059 which covers 'Command and Scripting Interpreter' as attackers may use such capabilities to establish persistent access or escalate their privileges further.
Mitigation strategies for CVE-2020-8738 primarily involve updating the BIOS firmware to versions provided by Intel that address the improper conditions check in the platform sample code. System administrators should prioritize applying the latest BIOS updates from Intel, which typically include corrected implementations of the privilege validation mechanisms. Additionally, organizations should implement strict access controls to limit local system access, particularly to systems running affected processors. Monitoring for unusual privilege escalation attempts and implementing robust logging of system changes can help detect potential exploitation attempts. Security teams should also consider implementing micro-segmentation and least privilege principles to limit the potential impact of any successful exploitation, as the vulnerability specifically targets local access scenarios where attackers already have some level of system access. Regular vulnerability assessments and firmware inventory management are essential to ensure all systems are running patched versions and to prevent similar issues from arising in future implementations.