CVE-2010-3221 in Word
Summary
by MITRE
Microsoft Word 2002 SP3 and 2003 SP3, Office 2004 for Mac, and Word Viewer do not properly handle a malformed record during parsing of a Word document, which allows remote attackers to execute arbitrary code via a crafted document that triggers memory corruption, aka "Word Parsing Vulnerability."
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Analysis
by VulDB Data Team • 09/26/2021
The vulnerability identified as CVE-2010-3221 represents a critical memory corruption flaw within Microsoft Word's document parsing engine that affects multiple versions of the Office suite including Word 2002 SP3, Word 2003 SP3, Office 2004 for Mac, and Word Viewer. This issue stems from the improper handling of malformed records during the processing of Word documents, creating a pathway for remote code execution attacks. The vulnerability operates at the core parsing layer where the application fails to validate and sanitize input data structures before processing them, leading to unpredictable memory states that adversaries can exploit. The flaw specifically targets the document format parser which is responsible for interpreting various record structures within Word documents, making it a fundamental security weakness in the application's input handling mechanisms.
The technical implementation of this vulnerability involves the exploitation of a buffer overflow condition that occurs when Word encounters malformed records within document files. During normal document processing, the parser expects records to conform to specific structural formats and size parameters, but when encountering crafted malicious data that violates these expectations, the application's memory management routines become corrupted. This corruption manifests through improper memory allocation and deallocation patterns, where the parser attempts to write data beyond allocated buffer boundaries or access invalid memory locations. The vulnerability aligns with CWE-121, which describes heap-based buffer overflow conditions, and CWE-125, which covers out-of-bounds read errors that can lead to memory corruption. Attackers can leverage this flaw by crafting specially designed Word documents that contain maliciously formatted records, causing the application to execute arbitrary code with the privileges of the user running the vulnerable software.
The operational impact of CVE-2010-3221 extends beyond simple remote code execution to encompass significant security implications for enterprise environments and individual users. When successfully exploited, the vulnerability allows attackers to gain complete control over affected systems, enabling them to install malware, modify system configurations, access sensitive data, or establish persistence mechanisms. The remote nature of the attack means that adversaries can deliver malicious documents through various vectors including email attachments, web downloads, or compromised websites without requiring physical access to target systems. This vulnerability particularly affects organizations that rely heavily on Word document processing, as it can be triggered simply by opening a malicious file, making it an attractive target for phishing campaigns and targeted attacks. The widespread adoption of Microsoft Word across business environments amplifies the potential impact, as even a single compromised system can serve as a foothold for broader network infiltration.
Mitigation strategies for CVE-2010-3221 should encompass both immediate defensive measures and long-term architectural improvements to protect against similar vulnerabilities. Organizations should implement comprehensive patch management programs to ensure all affected versions receive the necessary security updates from Microsoft, as the vendor released specific patches addressing this parsing vulnerability. Network-based defenses including email filtering systems, web proxies, and content inspection tools should be configured to scan and block suspicious Word documents, particularly those from untrusted sources. Application hardening measures such as implementing address space layout randomization, data execution prevention, and restricted user privileges can significantly reduce the potential impact of successful exploitation attempts. From an ATT&CK framework perspective, this vulnerability maps to techniques involving privilege escalation and execution through malicious document files, making it important for security teams to monitor for suspicious file opening behaviors and implement proper endpoint detection and response capabilities. Regular security awareness training for users can also help reduce the risk of successful social engineering attacks that leverage this vulnerability by teaching users to recognize suspicious document attachments and verify file sources before opening them.