CVE-2016-0021 in Office
Summary
by MITRE
Microsoft InfoPath 2007 SP3, 2010 SP2, and 2013 SP1 allows 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 • 07/09/2022
This vulnerability represents a critical memory corruption flaw in Microsoft InfoPath software versions 2007 SP3, 2010 SP2, and 2013 SP1 that enables remote code execution through maliciously crafted Office documents. The vulnerability stems from insufficient input validation and memory management within the InfoPath application when processing specially crafted Office file formats. Attackers can exploit this weakness by delivering a malicious document that, when opened by an affected InfoPath version, triggers a buffer overflow or memory corruption condition. This flaw falls under the CWE-121 CWE category for buffer overflow conditions, specifically representing a heap-based buffer overflow that can be leveraged to execute arbitrary code with the privileges of the targeted user. The attack vector is particularly dangerous as it requires no user interaction beyond opening the malicious document, making it a prime target for phishing campaigns and social engineering attacks. The vulnerability exposes a fundamental weakness in Microsoft's document processing architecture where the application fails to properly validate the structure and content of Office documents before attempting to parse and render them.
The technical exploitation of this vulnerability occurs when InfoPath attempts to parse a crafted document that contains malformed data structures designed to overwrite memory locations. The memory corruption typically manifests through stack or heap corruption that can be manipulated to redirect program execution flow to malicious code injected by the attacker. This type of vulnerability is classified under the ATT&CK technique T1203 - Exploitation for Client Execution, which specifically addresses how adversaries leverage software vulnerabilities to execute code on target systems. The exploitation process involves crafting a document that, when processed by the vulnerable InfoPath application, causes the application to allocate memory incorrectly or access memory beyond its allocated boundaries, ultimately leading to code execution. The vulnerability's impact is amplified by the fact that InfoPath is commonly used in enterprise environments for form processing and data collection, making it a valuable target for attackers seeking to compromise corporate networks.
The operational impact of this vulnerability extends beyond simple code execution to encompass complete system compromise and data exfiltration capabilities. Once successfully exploited, attackers can establish persistent access, escalate privileges, and move laterally within network environments. The vulnerability affects organizations that rely on InfoPath for business processes, particularly those handling sensitive data through form-based workflows. Security professionals should note that this vulnerability was patched as part of Microsoft's regular security updates, but organizations may still be at risk if they have not applied the necessary patches. The attack scenario typically involves an initial compromise through a phishing email containing the malicious document, followed by the exploitation of the memory corruption vulnerability to gain unauthorized access. Organizations should implement layered security controls including email filtering, application whitelisting, and regular patch management to protect against this and similar vulnerabilities. The vulnerability demonstrates the importance of maintaining up-to-date security patches and implementing defense-in-depth strategies to protect against exploitation of known vulnerabilities in widely used enterprise applications.
This vulnerability exemplifies the broader category of zero-day exploits that target memory corruption flaws in Microsoft Office applications, representing a significant challenge for enterprise security teams. The exploitation of such vulnerabilities requires constant vigilance and proactive security measures including regular security assessments, monitoring for anomalous network activity, and maintaining current threat intelligence feeds. Organizations should also consider implementing sandboxing technologies and privileged access management controls to limit the potential impact of successful exploitation attempts. The vulnerability's classification as a remote code execution flaw places it in the high-risk category for enterprise environments, where the potential for widespread compromise exists due to the prevalence of InfoPath applications in business processes. Security teams must also consider the broader implications of this vulnerability within the context of the ATT&CK framework, particularly in relation to initial access and execution phases of the cyber kill chain.