threat-modeling.md

Threat Model Analysis for kotlin/kotlinx.cli

Threat: Argument Injection via Parsed Arguments

Description: An attacker crafts malicious command-line arguments that are parsed by kotlinx.cli. If the application subsequently uses these parsed arguments to construct commands or queries for execution (e.g., shell commands, database interactions) without proper sanitization, the attacker can inject arbitrary commands or code. kotlinx.cli itself is not vulnerable, but it serves as the input vector, allowing malicious arguments to be processed and potentially exploited by the application's logic that relies on the parsed output from kotlinx.cli.

Impact: Remote Code Execution, data breach, system compromise, privilege escalation, depending on how the application utilizes the parsed arguments from kotlinx.cli.

Affected kotlinx.cli Component: Indirectly affects the entire kotlinx.cli parsing process as it's the entry point for malicious input. The vulnerability manifests in the application's usage of the parsed results.

Risk Severity: Critical

Mitigation Strategies:

• Avoid constructing commands or queries by directly concatenating parsed arguments obtained from kotlinx.cli.
• Utilize parameterized queries or prepared statements when interacting with databases, regardless of the input source, including arguments parsed by kotlinx.cli.
• If shell command execution is necessary, employ secure command execution methods that prevent injection, such as using libraries with proper argument escaping or avoiding shell execution altogether.
• Implement robust input validation and sanitization on the parsed arguments after they are processed by kotlinx.cli, before using them in any sensitive operations.

Threat: Security Misconfiguration of Argument Parsing Logic

Description: Developers may incorrectly configure the argument parsing logic within kotlinx.cli, leading to security vulnerabilities. This includes defining arguments with insufficient validation, missing required arguments that are crucial for security, or flawed custom validation logic using check() or validate() within kotlinx.cli argument definitions. An attacker can exploit these misconfigurations by providing specific command-line arguments that bypass intended security measures or manipulate application behavior in unintended and insecure ways due to the flawed parsing setup facilitated by kotlinx.cli.

Impact: Security bypass, unauthorized access to functionalities, application malfunction leading to exploitable states, potential for further attacks due to weakened security controls.

Affected kotlinx.cli Component: ArgParser configuration, argument definitions (ArgType, Arg), validation functions (check(), validate()) - all aspects related to how argument parsing is set up using kotlinx.cli.

Risk Severity: High

Mitigation Strategies:

• Thoroughly review and rigorously test the kotlinx.cli argument parsing configuration. Pay close attention to argument types, required arguments, and validation rules.
• Write comprehensive unit tests specifically for argument parsing logic, ensuring that the application behaves as expected for various valid and invalid input combinations, covering edge cases and potential bypass scenarios related to misconfiguration in kotlinx.cli.
• Use clear and well-documented argument descriptions within kotlinx.cli definitions to minimize the risk of misconfiguration and ensure developers understand the intended behavior and security implications of each argument.
• Conduct code reviews focusing specifically on the kotlinx.cli argument parsing setup to identify and rectify potential misconfigurations before deployment.