CVE-2016-7234 in Office
Summary
by MITRE
Microsoft Word 2007, Office 2010 SP2, Word 2010 SP2, Word 2013 SP1, Word 2013 RT SP1, Word for Mac 2011, Excel for Mac 2011, Word 2016 for Mac, Office Compatibility Pack SP3, Word Automation Services on SharePoint Server 2010 SP2, Word Automation Services on SharePoint Server 2013 SP1, Office Web Apps 2010 SP2, and Office Web Apps Server 2013 SP1 allow remote attackers to execute arbitrary code via a crafted Office document, aka "Microsoft Office Memory Corruption Vulnerability."
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Analysis
by VulDB Data Team • 09/30/2022
This vulnerability represents a critical memory corruption flaw in Microsoft Office applications that affects multiple versions across different platforms and server environments. The vulnerability stems from improper handling of specially crafted Office documents during the parsing process, specifically within the Word application's memory management routines. Attackers can exploit this weakness by crafting malicious Office documents that trigger buffer overflows or other memory corruption conditions when opened by vulnerable applications. The flaw exists in the way Microsoft Office applications process certain document structures and metadata, creating opportunities for arbitrary code execution in the context of the currently logged-on user.
The technical nature of this vulnerability aligns with CWE-121, which describes stack-based buffer overflow conditions, and CWE-122, which covers heap-based buffer overflow scenarios. These memory corruption vulnerabilities typically occur when applications fail to properly validate input data lengths before copying data into fixed-length memory buffers. The attack vector is particularly dangerous because it leverages social engineering techniques where users are tricked into opening seemingly legitimate Office documents that contain malicious payload code. The exploitation process often involves crafting documents with malformed structures that cause the application to allocate insufficient memory for processing, leading to memory corruption that can be leveraged to execute arbitrary code.
The operational impact of this vulnerability extends across enterprise environments where Office documents are frequently shared and opened, making it a significant threat to organizational security. Attackers can leverage this vulnerability to gain unauthorized access to systems, escalate privileges, and potentially establish persistent backdoors within networks. The vulnerability affects not only desktop Office applications but also server-side automation services including SharePoint Word Automation Services and Office Web Apps, amplifying the potential attack surface. Organizations running these vulnerable versions face risks of data breaches, system compromise, and lateral movement within their networks, particularly when users open malicious documents from untrusted sources or through phishing campaigns.
Mitigation strategies should focus on immediate patch deployment for all affected Microsoft Office versions, including the Office Compatibility Pack and server components. Network segmentation and email filtering solutions should be enhanced to block potentially malicious Office documents before they reach end users. Implementing application whitelisting policies can prevent unauthorized Office applications from executing, while regular security awareness training helps users recognize suspicious documents. Organizations should also consider disabling Office document automatic opening features and implementing strict document validation procedures. According to ATT&CK framework technique T1204.002, this vulnerability could be exploited through legitimate user execution paths, making user behavior monitoring essential for early detection of potential exploitation attempts. The vulnerability demonstrates the importance of maintaining up-to-date security patches and implementing defense-in-depth strategies to protect against sophisticated attack vectors that target widely used productivity applications.