CVE-2015-6093 in Office
Summary
by MITRE
Microsoft Office 2007 SP3, Office 2010 SP2, Office 2013 SP1, Office 2013 RT SP1, Office 2016, Word Automation Services on SharePoint Server 2010 SP2 and 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 • 06/27/2022
This vulnerability represents a critical memory corruption flaw in Microsoft Office applications that affects multiple versions including Office 2007 SP3 through Office 2016, along with various SharePoint and Web Apps components. The vulnerability stems from improper handling of specially crafted Office documents that trigger memory corruption during document processing, allowing remote attackers to execute arbitrary code on affected systems. The flaw specifically impacts Word Automation Services and Office Web Apps which are commonly used in enterprise environments for document processing and web-based office functionality. According to CWE-125, this vulnerability falls under the category of "Out-of-bounds Read" where the application fails to properly validate input data during document parsing operations, leading to memory corruption that can be exploited for code execution.
The technical exploitation of this vulnerability occurs when a user opens or previews a maliciously crafted Office document, typically through web-based interfaces or automated processing services. Attackers can leverage this flaw by embedding specially constructed malicious content within Word documents that, when processed by vulnerable Office components, causes buffer overflows or memory corruption that can be leveraged to inject and execute malicious code. The attack vector is particularly dangerous in enterprise environments where SharePoint servers and Office Web Apps are used for document collaboration and processing, as these services often automatically process documents without user interaction. This vulnerability aligns with ATT&CK technique T1203, "Exploitation for Client Execution," which describes how attackers use vulnerabilities in client applications to execute code remotely.
The operational impact of this vulnerability extends beyond simple code execution to encompass potential full system compromise and data breaches in enterprise environments. Organizations using affected Office versions are at risk of unauthorized access, data exfiltration, and persistent backdoor establishment when users open malicious documents. The widespread adoption of SharePoint and Office Web Apps makes this vulnerability particularly dangerous as it can be exploited through web-based attack vectors without requiring user interaction for initial compromise. Security teams face significant challenges in defending against this threat due to the broad range of affected products and the difficulty in preventing all possible attack vectors through document filtering alone. The vulnerability demonstrates the critical importance of timely patch management and the risks associated with legacy Office versions that may not receive continued security updates. Organizations should implement comprehensive security measures including network segmentation, document validation policies, and regular security assessments to mitigate the risk of exploitation.
Microsoft addressed this vulnerability through multiple security updates released in 2015, emphasizing the need for immediate patch deployment across all affected Office versions and server components. The vulnerability serves as a prime example of why organizations must maintain robust patch management processes and why legacy software components should be migrated to supported versions to avoid exposure to known security flaws. Security professionals should monitor for indicators of compromise related to this vulnerability and ensure that all Office-related services are properly updated to prevent exploitation attempts. The incident highlights the importance of defending against memory corruption vulnerabilities through proper input validation and secure coding practices, as these flaws represent some of the most persistent and dangerous classes of security vulnerabilities in enterprise software environments.