CVE-2016-0022 in Office
Summary
by MITRE
Microsoft Word 2007 SP3, Office 2010 SP2, Word 2010 SP2, Word 2013 SP1, Word 2013 RT SP1, Word 2016, Word for Mac 2011, Word 2016 for Mac, Office Compatibility Pack SP3, Word Viewer, Word Automation Services on SharePoint Server 2013 SP1, Office Web Apps Server 2013 SP1, and SharePoint Server 2013 SP1 allow remote attackers to execute arbitrary code via a crafted Office document, aka "Microsoft Office Memory Corruption Vulnerability," a different vulnerability than CVE-2016-0052.
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Analysis
by VulDB Data Team • 07/07/2022
The vulnerability described in CVE-2016-0022 represents a critical memory corruption flaw within Microsoft Office applications that affects multiple versions spanning from Office 2007 through Word 2016 across various platforms including Windows and Mac operating systems. This vulnerability specifically impacts the way Microsoft Word processes certain Office document formats, creating a condition where maliciously crafted documents can trigger memory corruption that adversaries can exploit to execute arbitrary code on target systems. The flaw exists in the document parsing and rendering mechanisms that handle various file formats including .doc, .docx, and other Office document types, making it particularly dangerous as it can be triggered through routine document opening operations. The vulnerability is classified as a memory corruption issue that falls under the CWE-125 vulnerability type, which represents out-of-bounds read conditions that can lead to arbitrary code execution. This particular vulnerability is distinct from CVE-2016-0052 and represents a separate but equally serious memory corruption flaw that has been actively exploited in the wild.
The technical exploitation of CVE-2016-0022 occurs when a user opens a specially crafted malicious Office document that contains malformed data structures designed to trigger memory corruption during the parsing process. Attackers typically construct documents with malformed headers, embedded objects, or corrupted data structures that cause the Word application to access memory locations outside of its intended boundaries. When the vulnerable application attempts to process these malformed elements, it can lead to buffer overflows, heap corruption, or other memory management issues that allow attackers to overwrite critical memory segments. The exploitation mechanism leverages the inherent trust users place in Office documents, making social engineering attacks particularly effective as users may unknowingly open malicious documents they receive through email attachments, file sharing, or web downloads. This vulnerability can be weaponized through various attack vectors including phishing campaigns, drive-by downloads, and malicious file sharing platforms that distribute infected Office documents.
The operational impact of CVE-2016-0022 extends beyond simple code execution to encompass full system compromise and potential lateral movement within enterprise networks. Successful exploitation can result in unauthorized access to sensitive data, persistence mechanisms being established, and the ability to escalate privileges within the compromised system. The vulnerability's widespread presence across multiple Office versions and platforms makes it particularly attractive to threat actors who can target organizations using different Office configurations and operating systems. Organizations with legacy systems running older versions of Office are especially vulnerable as these versions may not have received the necessary security updates or patches to address this specific memory corruption flaw. The vulnerability can also enable attackers to bypass security controls such as application whitelisting and exploit protection mechanisms, as the malicious code executes within the legitimate Office application process. From an attacker perspective, this vulnerability aligns with the MITRE ATT&CK framework's technique T1059.005 for command and script interpreter, as well as T1068 for exploit for privilege escalation, making it a versatile tool for advanced persistent threat actors.
Mitigation strategies for CVE-2016-0022 require a multi-layered approach combining immediate patching efforts with network and endpoint security controls. Microsoft released security updates that address this vulnerability through patches available in the Microsoft Security Response Center, requiring organizations to apply these updates promptly across all affected Office installations. Network segmentation and email filtering controls should be enhanced to prevent the delivery of potentially malicious Office documents through email systems, while application whitelisting policies can help prevent execution of untrusted Office documents. Organizations should implement strict document handling policies that require verification of document sources and content before opening, particularly for documents received from external parties or unknown sources. Endpoint detection and response solutions should be configured to monitor for suspicious Office process behavior, memory access patterns, and potential exploitation attempts. Regular security awareness training should be conducted to educate users about the risks of opening untrusted Office documents and the importance of verifying document authenticity. The vulnerability's presence across multiple Office versions also necessitates comprehensive inventory management to identify all affected systems and ensure complete remediation across the entire enterprise environment, as the attack surface is extensive and includes not just desktop installations but also server-based Office Web Apps and SharePoint environments that may be vulnerable to similar exploitation techniques.