CVE-2016-0054 in Office
Summary
by MITRE
Microsoft Excel 2007 SP3, Excel 2010 SP2, Excel 2013 SP1, Excel 2013 RT SP1, Excel 2016, Excel for Mac 2011, Excel 2016 for Mac, Office Compatibility Pack SP3, Excel Viewer, Excel Services on SharePoint Server 2007 SP3, Excel Services on SharePoint Server 2010 SP2, Excel Services on SharePoint Server 2013 SP1, and Office Web Apps 2010 SP2 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 • 07/07/2022
This vulnerability represents a critical memory corruption flaw in Microsoft Excel applications across multiple versions and platforms. The issue stems from improper handling of specially crafted Office documents that trigger buffer overflows or memory corruption conditions during document parsing operations. Attackers can exploit this weakness by preparing malicious Excel files containing malformed data structures that cause the application to improperly manage memory allocation and access patterns. The vulnerability affects not only standalone Excel installations but also integrated components such as Excel Services on SharePoint servers and Office Web Apps, expanding the potential attack surface significantly.
The technical nature of this flaw aligns with CWE-125, which describes out-of-bounds read conditions, and CWE-787, which covers out-of-bounds write operations. These memory corruption issues typically occur when the Excel application fails to properly validate input data from Office documents, particularly in parsing complex spreadsheet elements such as formulas, cell references, or embedded objects. The vulnerability allows attackers to manipulate memory pointers and execute arbitrary code with the privileges of the targeted user, potentially leading to complete system compromise. The attack requires the user to open the malicious document, making social engineering a critical component of successful exploitation.
From an operational impact perspective, this vulnerability poses significant risk to enterprise environments where Excel is commonly used for document sharing and collaboration. The attack vector through Office documents means that users can be compromised simply by opening seemingly legitimate files, making this a particularly dangerous flaw for organizations with less sophisticated security awareness training. The vulnerability affects both desktop and server components, meaning that even isolated systems that only run SharePoint services can be at risk. Organizations using Excel Services or Office Web Apps are particularly vulnerable since these components often run with elevated privileges and may be accessible from external networks.
Mitigation strategies should focus on immediate patch deployment across all affected Microsoft Office versions and platforms. Microsoft released security updates that address this vulnerability through proper input validation and memory management improvements. Organizations should implement strict document validation policies and consider deploying application whitelisting solutions to prevent execution of untrusted Office files. Network-based protections such as email filtering and web application firewalls can help reduce the likelihood of malicious documents reaching end users. Additionally, regular security awareness training should emphasize the dangers of opening unexpected Office documents, particularly those received via email or downloaded from untrusted sources. The vulnerability demonstrates the importance of maintaining current security patches and implementing defense-in-depth strategies that protect against various attack vectors including memory corruption exploits.