CVE-2016-0047 in Windows
Summary
by MITRE
WinForms in Microsoft .NET Framework 2.0 SP2, 3.5, 3.5.1, 4.5.2, 4.6, and 4.6.1 allows remote attackers to obtain sensitive information from process memory via crafted icon data, aka "Windows Forms Information Disclosure Vulnerability."
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Analysis
by VulDB Data Team • 07/07/2022
The vulnerability identified as CVE-2016-0047 represents a critical information disclosure flaw within Microsoft Windows Forms components of the .NET Framework ecosystem. This vulnerability specifically affects multiple versions of the .NET Framework including 2.0 SP2, 3.5, 3.5.1, 4.5.2, 4.6, and 4.6.1, creating a widespread impact across numerous enterprise environments that rely on these frameworks for application development and deployment. The flaw manifests through the improper handling of crafted icon data within the WinForms graphical user interface components, which are fundamental building blocks for Windows applications developed using Microsoft's managed code platforms.
The technical root cause of this vulnerability lies in the insufficient validation and sanitization of icon data structures when processing graphical elements within the Windows Forms framework. When applications attempt to load or display specially crafted icon files, the underlying WinForms components fail to properly validate the data format and structure, leading to memory access violations that inadvertently expose sensitive information from the process memory space. This occurs because the framework's icon processing routines do not adequately check for malformed or malicious data patterns that could cause the system to leak memory contents, including potentially sensitive data such as cryptographic keys, authentication tokens, or other confidential application state information. The vulnerability is classified under CWE-200, which specifically addresses "Information Exposure" and represents a classic case of improper input validation leading to unintended data leakage.
The operational impact of CVE-2016-0047 extends beyond simple information disclosure, as it creates potential attack vectors for more sophisticated exploitation techniques. Remote attackers who can influence the icon data loaded by vulnerable applications can potentially extract sensitive information that could be used for further attacks including credential theft, privilege escalation, or system compromise. The vulnerability is particularly concerning in enterprise environments where applications may process user-uploaded content or third-party graphical assets, as these scenarios provide ideal conditions for exploitation. Attackers could craft malicious icon files that, when processed by vulnerable applications, would reveal memory contents to the attacker, potentially including session tokens, database connection strings, or other critical system information. This type of vulnerability aligns with ATT&CK technique T1005, which involves "Data from Local System" and demonstrates how information disclosure vulnerabilities can serve as initial access vectors for broader compromise operations.
Mitigation strategies for CVE-2016-0047 require immediate attention from organizations running affected .NET Framework versions. Microsoft released security updates that address this vulnerability through proper input validation and memory handling improvements in the WinForms components. Organizations should prioritize applying the relevant security patches from Microsoft's security bulletin MS16-019 to remediate the issue across their environments. Additionally, administrators should implement network segmentation and access controls to limit the exposure of vulnerable applications to untrusted data sources. Application developers should review their code for proper input validation and consider implementing additional defensive measures such as sandboxing or strict content filtering for icon and graphical asset processing. The vulnerability demonstrates the importance of proper secure coding practices and input validation in managed code environments, particularly when dealing with user-supplied data that may be processed through framework components. Security monitoring should be enhanced to detect unusual memory access patterns or potential exploitation attempts targeting this specific vulnerability class.