Evil Clippy: A Cross-Platform Assistant for Creating Malicious MS Office Documents
If you’ve ever wondered how attackers create malicious Microsoft Office documents, look no further than Evil Clippy. This powerful and cross-platform assistant enables users to hide VBA macros, stomp VBA code, and confuse macro analysis tools with ease. Developed by Outflank and with significant contributions from the Walmart security team, Evil Clippy is designed for authorized testing and educational purposes in the areas of cybersecurity and Microsoft Office document manipulation.
Features and Functionalities
Evil Clippy offers a range of features and functionalities that make it a go-to tool for security professionals and enthusiasts alike:
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Hiding VBA Macros: Evil Clippy allows users to hide VBA macros from the GUI editor, making it difficult for analysts to detect and analyze potential malicious code.
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VBA Stomping: By abusing the P-code feature of module streams, Evil Clippy can replace P-code with fake VBA code, making it challenging for detection tools to decipher the original intent of the code.
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Fool Analyst Tools: Evil Clippy sets random ASCII module names in the dir stream, effectively tricking most P-code and VBA analysis tools into crashing, while allowing the actual code to run without interference in Word and Excel.
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HTTP Server: Evil Clippy can serve VBA stomped templates via an HTTP server, ensuring that the retrieved file matches the target’s Office version based on its HTTP headers.
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VBA Project Protection: Evil Clippy provides options to set or remove VBA project locked/unviewable protection attributes on Microsoft Word and Excel documents.
Target Audience and Use Cases
Evil Clippy caters to a diverse audience, including security professionals, penetration testers, and educational enthusiasts. This tool can be used for authorized testing of Microsoft Office document security, analyzing the effectiveness of antivirus products, and understanding the techniques used by attackers to evade detection.
Real-world use cases for Evil Clippy include:
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Penetration Testing: Security teams can use Evil Clippy to evaluate the effectiveness of their organization’s defenses by creating malicious documents that bypass antivirus products and maldoc analysis tools.
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Security Training: Evil Clippy can serve as a valuable educational resource to help train security professionals and raise awareness about potential threats related to Microsoft Office documents.
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Vulnerability Research: Researchers and analysts can utilize Evil Clippy to explore the limitations of existing security measures and identify novel attack vectors.
Technical Specifications and Innovations
Evil Clippy utilizes the OpenMCDF library to manipulate MS Office Compound File Binary Format (CFBF) files, while adhering to the MS-OVBA specifications for VBA macro manipulation. It also incorporates code from the Kavod.VBA.Compression library for implementing the compression algorithm used in dir and module streams.
One of the unique aspects of Evil Clippy is its cross-platform compatibility. It can be compiled and run on Linux, OSX, and Windows, thanks to its perfect compatibility with the Mono C# compiler and the Visual Studio compiler.
Competitive Analysis and Key Differentiators
Evil Clippy stands out among its competition due to its comprehensive features, cross-platform compatibility, and effectiveness in evading detection by major antivirus products and maldoc analysis tools. While other tools may offer some similar functionalities, Evil Clippy excels in its ability to hide VBA macros, abuse P-code, and confuse macro analysis tools, making it an invaluable asset for both offensive security activities and educational purposes.
Compatibility and Integration
Evil Clippy is designed for use with Microsoft Word and Excel for document manipulation. It supports a wide range of Office versions, ensuring compatibility with various environments.
Security Features and Compliance
Since Evil Clippy is primarily used for authorized testing and educational purposes, security features focus on detecting and exploiting potential vulnerabilities in Microsoft Office documents. While Evil Clippy is effective at evading antivirus products and maldoc analysis tools, it is crucial to handle this tool responsibly and ethically to minimize any potential harm.
Evil Clippy adheres to compliance standards by providing users with the necessary knowledge and tools to understand and mitigate security risks associated with Microsoft Office documents.
Performance Benchmarks and Roadmap
As of now, Evil Clippy has successfully bypassed most major antivirus products and maldoc analysis tools when used with default Cobalt Strike macros. However, detailed performance benchmarks are not available at this time.
In terms of the roadmap, the Outflank team is actively maintaining and updating Evil Clippy. Future updates may include enhancements to existing features, the addition of new capabilities, and further optimizations.
Conclusion and Final Pitch
Evil Clippy is an essential tool for any security professional or educational enthusiast interested in exploring the world of Microsoft Office document security. With its extensive features, cross-platform compatibility, and effectiveness in evading detection, Evil Clippy offers a unique advantage for authorized testing and learning purposes.
By utilizing Evil Clippy, users can gain valuable insights into the techniques used by attackers, evaluate the effectiveness of existing security measures, and stay ahead of potential threats. However, it is crucial to use this tool responsibly and ethically, strictly for authorized purposes.
Empower yourself with Evil Clippy and take your Microsoft Office security to the next level!
Get started with Evil Clippy by checking out the official GitHub repository: Evil Clippy
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