CVE-2021-34397 in Jetson
Summary
by MITRE • 06/23/2021
Bootloader contains a vulnerability in NVIDIA MB2, which may cause free-the-wrong-heap, which may lead to limited denial of service.
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Analysis
by VulDB Data Team • 06/26/2021
The vulnerability identified as CVE-2021-34397 resides within the NVIDIA MB2 bootloader component, representing a critical security flaw that impacts the foundational boot process of affected systems. This vulnerability specifically manifests in the memory management operations of the bootloader, where improper heap allocation and deallocation mechanisms create opportunities for memory corruption. The issue stems from how the bootloader handles memory requests during the boot sequence, particularly when managing dynamic memory allocation for various system components. The flaw allows for potential memory management inconsistencies that could be exploited to disrupt normal system operation.
The technical implementation of this vulnerability involves improper handling of memory deallocation processes within the NVIDIA MB2 bootloader. When the system attempts to free memory allocated during the boot process, the bootloader may inadvertently free memory that was not properly allocated or that has already been freed, creating a condition known as double-free or free-the-wrong-heap. This memory management error occurs during the early boot stages when the system is establishing critical runtime environments and can be triggered through specific sequences of boot operations or memory allocation patterns. The vulnerability is particularly concerning because it operates at the bootloader level, which means it can affect system integrity before the operating system has fully initialized and implemented standard security protections.
The operational impact of CVE-2021-34397 manifests primarily as limited denial of service conditions, where affected systems may experience boot failures, system instability, or complete inability to boot properly. While the vulnerability does not appear to enable arbitrary code execution or direct privilege escalation, its location within the bootloader makes it particularly dangerous as it can prevent legitimate system operation entirely. The limited nature of the denial of service means that attackers cannot necessarily cause complete system compromise, but they can effectively render devices unusable until the bootloader is repaired or replaced. This type of vulnerability is especially problematic in embedded systems, IoT devices, and mobile platforms where bootloader integrity is critical for device functionality and where physical access to repair mechanisms may be limited.
The vulnerability aligns with CWE-415, which describes improper handling of memory allocation and deallocation operations leading to double-free conditions. From an adversarial perspective, this flaw can be mapped to ATT&CK technique T1068, which involves exploiting local privileges to gain system-level access through boot process manipulation. The attack surface is particularly relevant in environments where adversaries may have physical access to devices or where remote exploitation pathways exist through firmware update mechanisms. Organizations should implement comprehensive firmware update policies and ensure that bootloader components are regularly patched and validated. The vulnerability highlights the importance of secure boot processes and proper memory management practices within low-level system components, emphasizing the need for thorough security testing of bootloader implementations.
Mitigation strategies should focus on immediate firmware updates from NVIDIA and system administrators should prioritize patching affected devices as soon as updates become available. The remediation process requires careful attention to ensure that bootloader updates do not introduce compatibility issues with existing hardware configurations. Organizations should also consider implementing additional monitoring mechanisms to detect abnormal boot behavior that might indicate exploitation attempts. Regular security assessments of embedded system firmware and boot processes should be conducted to identify similar vulnerabilities. The incident underscores the critical importance of maintaining secure development practices for low-level system components and highlights the necessity of robust security testing throughout the entire software development lifecycle, particularly for components that operate outside of normal operating system protections.