CVE-2008-0109 in Office
Summary
by MITRE
Word in Microsoft Office 2000 SP3, XP SP3, Office 2003 SP2, and Office Word Viewer 2003 allows remote attackers to execute arbitrary code via crafted fields within the File Information Block (FIB) of a Word file, which triggers length calculation errors and memory corruption.
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Analysis
by VulDB Data Team • 06/01/2025
This vulnerability resides in the Microsoft Office Word processing engine and represents a classic buffer overflow condition that can be exploited remotely through maliciously crafted Word documents. The flaw specifically affects multiple versions of Microsoft Office including Office 2000 SP3, XP SP3, Office 2003 SP2, and Office Word Viewer 2003, making it particularly dangerous due to the widespread deployment of these software versions across enterprise environments. The vulnerability is triggered when the Word application processes the File Information Block (FIB) structure within a Word document, which contains metadata about the document's internal structure and formatting information. When the application encounters crafted fields within this block, it performs incorrect length calculations that lead to memory corruption, ultimately allowing remote attackers to execute arbitrary code with the privileges of the user running the vulnerable software. This type of vulnerability falls under CWE-121, which describes stack-based buffer overflow conditions, and also aligns with CWE-125, representing out-of-bounds read conditions that can lead to memory corruption. The attack vector is particularly concerning because it requires no user interaction beyond opening the malicious document, making it susceptible to automated exploitation campaigns. From an operational perspective, this vulnerability represents a significant risk to enterprise security as it can be delivered through email attachments, web downloads, or malicious file sharing, and the exploitation can occur without any user awareness or intervention. The memory corruption aspect of this vulnerability makes it particularly dangerous because it can lead to complete system compromise, allowing attackers to gain full control over affected systems. The vulnerability has been mapped to multiple ATT&CK techniques including T1203, which covers exploitation for execution, and T1059, which involves command and scripting interpreter usage, as attackers can leverage the arbitrary code execution to establish persistent access. The root cause of this issue stems from inadequate input validation within the FIB parsing logic, where the application fails to properly validate the length fields in the crafted malicious data, leading to buffer overflows that can be exploited to overwrite critical memory locations. Microsoft addressed this vulnerability through security updates that corrected the length calculation logic and implemented additional bounds checking mechanisms to prevent the memory corruption from occurring. Organizations should prioritize patching affected systems and consider implementing additional security controls such as email filtering, document validation, and network-based protection mechanisms to mitigate the risk of exploitation. The vulnerability demonstrates the critical importance of proper input validation and memory management in office productivity applications, as these tools are frequently targeted by attackers due to their widespread use and the potential for privilege escalation when exploited successfully.