CVE-2007-2884 in Visual Basic
Summary
by MITRE
Multiple stack-based buffer overflows in Microsoft Visual Basic 6 allow user-assisted remote attackers to cause a denial of service (CPU consumption) or execute arbitrary code via a Visual Basic Project (vbp) file with a long (1) Description or (2) Company Name (VersionCompanyName) field.
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Analysis
by VulDB Data Team • 09/18/2024
Microsoft Visual Basic 6 contains multiple stack-based buffer overflow vulnerabilities that arise from insufficient input validation in the handling of Visual Basic Project files. These flaws specifically affect the Description and Company Name fields within vbp files, where maliciously crafted long strings can exceed the allocated buffer space and overwrite adjacent memory locations. The vulnerability operates through a user-assisted remote attack vector, meaning that an attacker must convince a victim to open a specially crafted vbp file for the exploit to succeed. The buffer overflow conditions occur during the parsing of project metadata fields, where the application fails to properly bounds-check string inputs before copying them into fixed-size memory buffers on the stack.
The technical implementation of these vulnerabilities stems from the lack of proper input sanitization in Visual Basic 6's project file parser. When a vbp file is loaded, the application reads the Description and VersionCompanyName fields and attempts to store them in predetermined buffer sizes without adequate validation. This classic stack-based buffer overflow allows attackers to overwrite return addresses and potentially execute arbitrary code with the privileges of the victim user. The vulnerability is particularly concerning because Visual Basic 6 was widely used in enterprise environments and legacy systems, making it a valuable target for attackers seeking persistent access to corporate networks. The memory corruption can also manifest as denial of service conditions, causing the application to consume excessive CPU resources or crash entirely, effectively disrupting normal operations.
The operational impact of CVE-2007-2884 extends beyond simple exploitation capabilities as it represents a significant security weakness in legacy development environments that persist in many organizations. Attackers can leverage these vulnerabilities to establish persistent backdoors through code execution, potentially gaining access to sensitive corporate data or using the compromised system as a launch point for further attacks within the network. The user-assisted nature of the attack means that social engineering components are required, but this makes the vulnerability particularly dangerous in targeted campaigns where attackers can convince users to open malicious project files. Organizations running Visual Basic 6 applications face increased risk of data breaches and system compromise, especially in environments where legacy software remains in active use without proper security controls. This vulnerability aligns with attack patterns documented in the mitre attack framework under initial access and execution techniques, specifically targeting legacy software environments that may not receive regular security updates.
Mitigation strategies for this vulnerability require immediate action to address the root cause through proper input validation and bounds checking in the affected applications. Organizations should implement strict file validation policies that prevent the loading of untrusted vbp files or apply sandboxing techniques to isolate Visual Basic 6 execution environments. The most effective long-term solution involves migrating away from legacy Visual Basic 6 development environments to modern platforms that receive regular security updates and have better memory protection mechanisms. Security patches for Visual Basic 6 are no longer available from Microsoft, making operational mitigations critical for organizations that must continue using these legacy systems. Network segmentation and user access controls can help limit the potential damage from successful exploitation, while regular security awareness training can reduce the likelihood of social engineering attacks succeeding against employees. The vulnerability demonstrates the importance of maintaining up-to-date security practices even for legacy systems and highlights the need for comprehensive software inventory management to identify and remediate similar risks across all organizational assets.