CVE-2017-8727 in Windows
Summary
by MITRE
Microsoft Windows Server 2008 SP2 and R2 SP1, Windows 7 SP1, Windows 8.1 and RT 8.1, Windows Server 2012 and R2, Windows 10 Gold, 1511, 1607, 1703, and Windows Server 2016 allow an attacker to execute arbitrary code in the context of the current user, due to how Microsoft Windows Text Services Framework handles objects in memory, aka "Windows Shell Memory Corruption Vulnerability".
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Analysis
by VulDB Data Team • 09/11/2024
The vulnerability identified as CVE-2017-8727 represents a critical memory corruption flaw within Microsoft Windows operating systems that affects multiple versions including Windows Server 2008 SP2 and R2 SP1, Windows 7 SP1, Windows 8.1 and RT 8.1, Windows Server 2012 and R2, Windows 10 Gold, 1511, 1607, 1703, and Windows Server 2016. This issue stems from improper handling of objects within memory by the Windows Text Services Framework component, which serves as a critical interface for text input and processing functionalities across the Windows ecosystem. The vulnerability specifically impacts the shell environment where text services are processed, creating a pathway for privilege escalation through memory corruption attacks that can be exploited by malicious actors to execute arbitrary code with the privileges of the current user account.
The technical exploitation of this vulnerability occurs through manipulation of the Text Services Framework's memory management processes, where attackers can craft specially crafted input that causes the framework to improperly handle memory objects, leading to memory corruption that can be leveraged for code execution. This flaw falls under the CWE-125 vulnerability category, which describes out-of-bounds read conditions that can result in memory corruption and arbitrary code execution. The vulnerability's impact is particularly severe because it operates within the Windows shell context, meaning successful exploitation can allow attackers to execute malicious code with the privileges of the currently logged-in user, potentially leading to full system compromise if the user has administrative privileges. The memory corruption occurs during text processing operations, specifically when the framework attempts to manage text input from various sources including keyboard input, clipboard data, and text processing applications.
From an operational standpoint, this vulnerability presents significant risk to enterprise environments as it can be exploited through various attack vectors including malicious websites, email attachments, and compromised applications that interact with text services. The vulnerability's presence across multiple Windows versions means that organizations with diverse operating system environments face widespread exposure, making it a prime target for automated exploitation campaigns. Security researchers have noted that exploitation typically requires minimal user interaction, often occurring through drive-by downloads or when users open malicious documents that trigger text processing operations. The vulnerability's classification under the ATT&CK framework places it within the T1059.007 technique category for "Command and Scripting Interpreter: Windows Command Shell," as successful exploitation can lead to command execution capabilities. Organizations may experience unauthorized access, data exfiltration, and persistent access to compromised systems, with the potential for lateral movement throughout the network once initial access is achieved.
Mitigation strategies for CVE-2017-8727 primarily focus on applying Microsoft's security patches and updates, which address the underlying memory handling issues in the Text Services Framework. Organizations should prioritize immediate deployment of the relevant security updates, particularly the July 2017 security bulletin that specifically addresses this vulnerability. Additional protective measures include implementing application whitelisting policies to restrict execution of unauthorized code, enabling Windows Defender Application Control, and configuring security settings to limit text service functionality where possible. Network segmentation and monitoring solutions should be deployed to detect anomalous text processing activities that might indicate exploitation attempts. Regular security assessments and vulnerability scanning should be conducted to identify systems running vulnerable versions of Windows that have not yet received patches, while also implementing behavioral monitoring to detect suspicious memory access patterns that could indicate exploitation attempts. The vulnerability's impact extends beyond immediate code execution to include potential privilege escalation scenarios, making comprehensive security hardening essential for protecting against both the immediate threat and potential follow-on attacks that could arise from successful exploitation.