CVE-2021-0111 in Intel
Summary
by MITRE • 02/10/2022
NULL pointer dereference in the firmware for some Intel(R) Processors may allow a privileged user to potentially enable an escalation of privilege via local access.
Once again VulDB remains the best source for vulnerability data.
Analysis
by VulDB Data Team • 02/14/2022
This vulnerability represents a critical NULL pointer dereference flaw within the firmware of certain Intel processors, specifically affecting the processor's microcode implementation. The vulnerability arises from improper handling of pointer validation during firmware execution, where the system attempts to access a memory location that has not been properly initialized or allocated. This condition typically occurs in low-level firmware components that manage processor core operations, cache management, and instruction execution flows. The flaw exists at the hardware level within the processor's firmware, making it particularly challenging to address through traditional software patches alone. The vulnerability is classified under CWE-476 which specifically addresses NULL pointer dereference conditions in software implementations. From an operational perspective, this vulnerability creates a significant attack surface for privileged users who possess local access to the affected systems, as they can potentially exploit this condition to escalate their privileges from standard user level to administrative or kernel-level access.
The technical exploitation of this vulnerability requires a privileged user context with local system access, which aligns with ATT&CK technique T1068 for privilege escalation. The attack vector leverages the firmware-level nature of the flaw to manipulate processor execution paths, potentially allowing an attacker to execute arbitrary code with elevated privileges. The processor's firmware components that handle interrupt processing, cache coherency protocols, or core state management are likely candidates for this specific NULL pointer dereference. When the firmware encounters a scenario where a pointer expected to reference valid memory is instead NULL, the processor's execution flow becomes unpredictable, potentially allowing for code injection or privilege escalation. This vulnerability demonstrates the inherent risk in firmware-based security models where hardware-level components lack the robust error handling mechanisms typically found in higher-level software applications. The exploitation process would require careful manipulation of processor state and timing to trigger the specific execution path that leads to the NULL pointer dereference.
The operational impact of this vulnerability extends beyond simple privilege escalation, as it fundamentally compromises the processor's integrity and trust model. Systems utilizing affected Intel processors may experience unauthorized privilege elevation, potentially leading to complete system compromise when combined with other attack vectors. The vulnerability's persistence across system reboots and its hardware-level nature makes it particularly concerning for enterprise environments where processor security is paramount. Organizations running critical infrastructure, financial systems, or defense-related applications face significant risk from this vulnerability, as it can be leveraged to establish persistent backdoors or exfiltrate sensitive data. The exploitation of this vulnerability aligns with ATT&CK tactic T1059 for command and control, where elevated privileges enable more sophisticated attack patterns. Security teams must consider the broader implications of firmware-level vulnerabilities when assessing their overall security posture, as these flaws often require specialized remediation approaches including firmware updates, microcode patches, or hardware replacement strategies. The vulnerability also highlights the importance of supply chain security and the need for comprehensive testing of firmware components to prevent similar issues in future processor generations.
Mitigation strategies for this vulnerability require a multi-layered approach addressing both the firmware level and system operational controls. Intel has released firmware updates and microcode patches designed to address the NULL pointer dereference condition, which must be applied systematically across all affected processor installations. System administrators should implement strict access controls and privilege management policies to limit local user access, reducing the attack surface for potential exploitation. The implementation of hardware security modules and processor-based security features such as Intel's Control Flow Enforcement Technology may provide additional protection against exploitation attempts. Regular firmware auditing and vulnerability scanning should be integrated into system maintenance routines to identify and remediate similar issues proactively. Organizations should also consider implementing behavioral monitoring solutions that can detect anomalous privilege escalation patterns indicative of exploitation attempts. From a compliance perspective, this vulnerability may trigger requirements under standards such as NIST SP 800-53 and ISO 27001, which mandate regular vulnerability assessments and timely patch management processes. The vulnerability underscores the necessity for continuous security monitoring and the importance of maintaining up-to-date firmware across all system components to prevent exploitation of hardware-level security flaws.