CVE-2020-8100 in BitDefender Engine
Summary
by MITRE
Improper Input Validation vulnerability in the cevakrnl.rv0 module as used in the Bitdefender Engines allows an attacker to trigger a denial of service while scanning a specially-crafted sample. This issue affects: Bitdefender Bitdefender Engines versions prior to 7.84063.
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Analysis
by VulDB Data Team • 10/18/2020
The CVE-2020-8100 vulnerability represents a critical improper input validation flaw within the cevakrnl rv0 module of Bitdefender Engines, specifically targeting versions prior to 7.84063. This vulnerability exists at the core of Bitdefender's antivirus scanning infrastructure where the cevakrnl rv0 module handles kernel-level operations during threat detection processes. The module's insufficient validation mechanisms create a pathway for malicious actors to exploit the system through carefully crafted malicious files that trigger unexpected behavior during the scanning procedure.
The technical implementation of this vulnerability stems from inadequate input sanitization within the kernel module responsible for processing potentially malicious samples. When the cevakrnl rv0 module encounters specially crafted input data, it fails to properly validate the structure and content of the scanned file, allowing malformed data to propagate through the system's validation layers. This weakness manifests as a denial of service condition where the module becomes unresponsive or crashes, effectively disabling the antivirus engine's ability to perform threat detection on subsequent samples. The vulnerability operates at the kernel level, making it particularly dangerous as it can compromise the stability of the entire security infrastructure.
The operational impact of this vulnerability extends beyond simple service disruption, as it represents a potential attack vector for adversaries seeking to evade detection or compromise security systems. Attackers can leverage this weakness to create targeted denial of service conditions against Bitdefender protected systems, potentially causing widespread disruption in enterprise environments where the antivirus engine is critical for security operations. The vulnerability affects the availability aspect of the CIA triad, as it can render the security solution ineffective during critical threat assessment phases. According to CWE classification, this vulnerability maps to CWE-20: Improper Input Validation, which is a fundamental weakness that allows attackers to manipulate system behavior through malformed inputs.
The attack surface for CVE-2020-8100 aligns with ATT&CK technique T1499.004: Endpoint Denial of Service, where adversaries target system resources to prevent legitimate use of endpoints. This vulnerability can be exploited through file-based attacks where malicious actors craft specific payloads designed to trigger the input validation bypass. The impact is particularly severe in enterprise environments where Bitdefender engines are deployed across multiple systems, as a single compromised endpoint could potentially affect broader network security operations. Organizations relying on Bitdefender's kernel-level protection mechanisms face significant risk from this vulnerability, as it undermines the fundamental security posture by creating conditions where the antivirus solution itself becomes a point of failure.
Mitigation strategies for CVE-2020-8100 require immediate implementation of the vendor-provided security update to version 7.84063 or later, which contains the necessary input validation fixes. Organizations should also implement network segmentation and monitoring to detect potential exploitation attempts, as well as maintain robust backup and recovery procedures to ensure business continuity during remediation. The vulnerability highlights the critical importance of regular security updates and proper input validation practices in kernel-level modules. Additionally, security teams should conduct thorough vulnerability assessments to identify any other potential input validation issues within similar security infrastructure components, as this vulnerability demonstrates the severe consequences that can arise from inadequate validation controls in core security modules.