threat-modeling.md

Threat Model Analysis for microsoft/win2d

Threat: Malformed Image Data Exploitation

Description: An attacker provides a maliciously crafted image file to the application. Win2D's image decoding or processing functions attempt to parse this file, triggering a vulnerability such as a buffer overflow or integer overflow. This could lead to memory corruption and potentially arbitrary code execution, allowing the attacker to gain control of the application or the system. Impact: Remote Code Execution (RCE), Denial of Service (DoS), Application Crash, potential system compromise. Win2D Component Affected: CanvasBitmap, CanvasRenderTarget, Image decoding functions (e.g., within CanvasBitmap.LoadAsync, CanvasRenderTarget.CreateBitmapFromBytes). Risk Severity: Critical Mitigation Strategies: * Implement robust input validation on image files before loading them with Win2D. * Utilize secure and up-to-date image decoding libraries within the application's environment. * Consider using image sanitization techniques to remove potentially malicious metadata or embedded code from image files. * Limit the file size and dimensions of images processed by the application.

Threat: Memory Corruption in Native Win2D Code

Description: Due to Win2D being a native library, vulnerabilities like buffer overflows, use-after-free, or other memory safety issues might exist within its code. An attacker could trigger these vulnerabilities by providing specific inputs or performing certain operations that expose these flaws in Win2D's native modules. Successful exploitation could lead to arbitrary code execution, allowing the attacker to take complete control of the application and potentially the underlying system. Impact: Remote Code Execution (RCE), Denial of Service (DoS), Application Crash, potential system compromise. Win2D Component Affected: Core Win2D native modules, potentially affecting various functions across the library. Risk Severity: Critical Mitigation Strategies: * Keep the Win2D library updated to the latest version to benefit from security patches and bug fixes released by Microsoft. * Monitor for security advisories related to Win2D and DirectX. * Report any suspected crashes or unexpected behavior to Microsoft for investigation.

Threat: Shader Code Injection (Custom Effects)

Description: If the application allows users to provide custom shader code (e.g., for custom effects or rendering pipelines), an attacker could inject malicious shader code. This code could be designed to bypass security checks, access sensitive data within the graphics context, or potentially exploit vulnerabilities in Win2D's shader compilation or execution pipeline. In a worst-case scenario, this could lead to code execution within the graphics context or even escalate to system-level compromise. Impact: Remote Code Execution (RCE) (potential depending on exploitability), Information Disclosure, Denial of Service (DoS). Win2D Component Affected: CanvasEffect, ICustomEffect, Shader compilation and execution pipeline within Win2D. Risk Severity: High Mitigation Strategies: * Avoid allowing user-provided shader code if possible. * If custom shaders are necessary, implement strict validation and sanitization of shader code before compilation. * Enforce a secure shader compilation environment with limited privileges. * Consider using a whitelist of allowed shader operations or effects. * Regularly update graphics drivers to patch potential shader-related vulnerabilities, as shader exploits can sometimes leverage driver flaws.