CVE-2016-7274 in Windows
Summary
by MITRE
Uniscribe in Microsoft Windows Vista SP2, Windows Server 2008 SP2 and R2 SP1, Windows 7 SP1, Windows 8.1, Windows Server 2012 Gold and R2, Windows RT 8.1, Windows 10 Gold, 1511, and 1607, and Windows Server 2016 allows remote attackers to execute arbitrary code via a crafted web site, aka "Windows Uniscribe Remote Code Execution Vulnerability."
If you want to get best quality of vulnerability data, you may have to visit VulDB.
Analysis
by VulDB Data Team • 09/23/2024
The vulnerability identified as CVE-2016-7274 resides within Microsoft's Uniscribe text processing engine, which is integral to the Windows operating system's handling of complex text layouts and rendering operations. This flaw affects a broad range of Windows versions including Vista through Windows 10 and their respective server counterparts, making it particularly concerning from a security perspective due to its widespread presence across enterprise and consumer environments. The vulnerability specifically manifests in how Uniscribe processes certain Unicode text sequences, particularly those involving complex script rendering operations that are commonly encountered on modern web pages.
The technical exploitation of this vulnerability occurs through a carefully crafted web page that leverages specific Unicode character sequences and text formatting operations that trigger memory corruption within the Uniscribe component. When a victim visits such a malicious website, the browser's rendering engine processes the page content through Uniscribe, which fails to properly validate input parameters during complex text layout calculations. This improper validation leads to a buffer overflow condition or other memory corruption scenarios that can be leveraged by remote attackers to execute arbitrary code with the privileges of the affected user. The vulnerability falls under CWE-121, which describes heap-based buffer overflow conditions, and represents a classic example of how text processing libraries can become attack vectors when input validation is insufficient.
From an operational standpoint, this vulnerability presents significant risk to organizations since it requires no user interaction beyond visiting a malicious website, making it particularly dangerous in phishing campaigns or compromised websites. The attack surface is extensive given that Uniscribe is used throughout Windows for rendering text in various applications including web browsers, word processors, and system interfaces. Attackers can craft web content that appears legitimate while simultaneously containing the malicious Unicode sequences designed to trigger the vulnerability. The impact extends beyond simple code execution to potentially allow full system compromise, as the executed code runs within the context of the user's privileges, which may be elevated in certain scenarios.
The exploitation of this vulnerability aligns with ATT&CK technique T1203, which involves exploitation of remote services through web-based attacks, and demonstrates how seemingly benign text rendering operations can become critical attack vectors. Organizations should implement immediate mitigations including applying the relevant Microsoft security updates that address the Uniscribe vulnerability, while also considering network-level protections such as web application firewalls that can detect and block malicious Unicode sequences. Additional defensive measures include implementing browser hardening configurations, restricting user privileges, and deploying endpoint detection and response solutions that can monitor for anomalous behavior associated with memory corruption exploits. The vulnerability serves as a reminder of the critical importance of validating all text input within system components and demonstrates how even fundamental text processing libraries can become targets for sophisticated exploitation techniques.