CVE-2012-0167 in Office
Summary
by MITRE
Heap-based buffer overflow in the Office GDI+ library in Microsoft Office 2003 SP3 and 2007 SP2 and SP3 allows remote attackers to execute arbitrary code via a crafted EMF image in an Office document, aka "GDI+ Heap Overflow Vulnerability."
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Analysis
by VulDB Data Team • 03/24/2021
The CVE-2012-0167 vulnerability represents a critical heap-based buffer overflow within Microsoft Office's Graphics Device Interface Plus GDI+ library implementation. This flaw exists specifically in Office 2003 Service Pack 3 and Office 2007 Service Packs 2 and 3, making it a legacy vulnerability that affected widely deployed software components. The vulnerability stems from inadequate input validation when processing Enhanced Metafile (EMF) image formats within Office documents, creating a condition where maliciously crafted image data can overwrite adjacent memory locations in the heap allocation space.
The technical exploitation of this vulnerability occurs through the manipulation of EMF image data embedded within Office documents such as Word, Excel, or PowerPoint files. When Office attempts to render these malicious EMF images using the GDI+ library, the insufficient bounds checking allows an attacker to write data beyond the allocated buffer boundaries. This heap corruption can result in arbitrary code execution with the privileges of the user running the vulnerable Office application, effectively providing attackers with a remote code execution capability that bypasses many traditional security controls.
From an operational perspective, this vulnerability presents significant risk to enterprise environments where Office documents are frequently exchanged and opened by multiple users. The attack vector requires only a single malicious document to be opened by an unsuspecting user, making it particularly dangerous in phishing campaigns or social engineering attacks. The vulnerability maps to CWE-121 Heap-based Buffer Overflow, which is classified as a fundamental memory safety issue that directly enables code execution attacks. This weakness is particularly concerning as it operates at the core graphics rendering layer of Office applications, making it difficult to detect through standard application-level security measures.
The attack surface extends beyond simple document opening to include any scenario where Office processes EMF graphics, including email attachments, shared network drives, and document collaboration platforms. Organizations using older versions of Office remain particularly vulnerable, as the patching cycle for these legacy applications has largely concluded. Security professionals should note this vulnerability's alignment with ATT&CK technique T1059.005 for command and scripting interpreter, as successful exploitation can lead to full system compromise. Mitigation strategies include implementing strict document validation policies, disabling automatic image rendering in email clients, deploying application whitelisting solutions, and ensuring all systems have received appropriate security updates. The vulnerability also underscores the importance of maintaining up-to-date security patches and demonstrates how graphics rendering components can serve as critical attack vectors in enterprise security architectures.