CVE-2008-4922 in Activex Control For Microsoft Office 2000
Summary
by MITRE
Buffer overflow in the DjVu ActiveX Control 3.0 for Microsoft Office (DjVu_ActiveX_MSOffice.dll) allows remote attackers to execute arbitrary code via a long (1) ImageURL property, and possibly the (2) Mode, (3) Page, or (4) Zoom properties.
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Analysis
by VulDB Data Team • 05/25/2025
The vulnerability identified as CVE-2008-4922 represents a critical buffer overflow flaw within the DjVu ActiveX Control 3.0 component designed for Microsoft Office environments. This security weakness resides in the DjVu_ActiveX_MSOffice.dll dynamic link library that facilitates integration of DjVu document viewing capabilities within office applications. The vulnerability manifests when the control processes user-supplied input through specific properties that are susceptible to excessive data input. The attack vector involves remote exploitation through web-based delivery mechanisms, making it particularly dangerous as it can be triggered without user interaction beyond visiting a malicious website or opening a specially crafted document.
The technical implementation of this buffer overflow occurs when the DjVu ActiveX Control processes the ImageURL property with excessively long input strings, potentially extending to other properties including Mode, Page, and Zoom. These properties are commonly used for configuring document display parameters and navigation within DjVu documents. The flaw stems from inadequate input validation and bounds checking within the control's memory management routines. When a maliciously crafted string exceeds the allocated buffer space, it overflows into adjacent memory regions, potentially corrupting critical program data or executable code. This memory corruption can be leveraged by attackers to overwrite return addresses, function pointers, or other critical control structures, thereby enabling arbitrary code execution with the privileges of the compromised application process.
The operational impact of this vulnerability extends beyond simple code execution, as it provides attackers with persistent access to systems through the compromised Microsoft Office environment. Since the control is designed to operate within the trusted context of office applications, successful exploitation can lead to complete system compromise without requiring additional privilege escalation. The vulnerability affects systems running vulnerable versions of the DjVu ActiveX Control, particularly those integrated into Microsoft Office suites where the control is enabled and accessible. This creates a significant risk for enterprise environments where office applications are commonly used and where users may inadvertently access malicious content through phishing campaigns or compromised websites.
Organizations should implement immediate mitigations including disabling the DjVu ActiveX Control in Microsoft Office environments where it is not essential for business operations. System administrators should consider implementing application whitelisting policies to prevent execution of untrusted ActiveX controls and ensure that all systems are patched with the latest security updates from the vendor. Network-based defenses should include filtering of potentially malicious content and monitoring for suspicious ActiveX control usage patterns. The vulnerability aligns with CWE-121, which describes stack-based buffer overflow conditions, and represents a classic example of how ActiveX controls can introduce security risks when not properly validated. From an ATT&CK framework perspective, this vulnerability maps to T1059.007 for execution through ActiveX components and T1068 for privilege escalation through application vulnerabilities, highlighting the multi-layered attack surface that such controls present in enterprise environments.