mitigations.md

Mitigation Strategies Analysis for textualize/rich

Mitigation Strategy: Sanitize User-Controlled Input Rendered by Rich

• Mitigation Strategy: Sanitize User-Controlled Input Rendered by Rich

• Description:

  1. Identify Rich Input Points: Locate all places in your application code where user-provided data is directly passed to rich rendering functions such as console.print(), console.log(), or when rendering Markdown content using rich.
  2. Choose Sanitization Method for Rich: Select a sanitization technique specifically aimed at mitigating risks within rich's rendering context. This primarily involves handling ANSI escape codes and potentially other formatting characters that rich interprets. Options include:
     • ANSI Escape Code Stripping: Use regular expressions (e.g., Python's re module) to remove ANSI escape codes from user input before passing it to rich. This prevents users from manipulating terminal output formatting through rich.
     • Character Whitelisting/Blacklisting (for Rich Context): If finer control is needed, implement whitelisting or blacklisting of specific characters relevant to rich's formatting, beyond just ANSI codes.
  3. Implement Rich Sanitization Function: Create a dedicated function that takes user input as a string and applies the chosen sanitization method specifically for use with rich. This function should be called before any user input is rendered by rich.
  4. Apply Rich Sanitization Before Rendering: In your code, ensure that the rich sanitization function is consistently applied to user input immediately before it is passed to any rich rendering function.
  5. Testing with Rich Rendering: Thoroughly test the sanitization function in conjunction with rich rendering. Verify that malicious ANSI escape codes and other potentially harmful formatting attempts are effectively neutralized when displayed using rich.

• Threats Mitigated:

  • ANSI Escape Code Injection via Rich (High Severity): Malicious users inject ANSI escape codes that are interpreted by rich to manipulate terminal output. This can lead to denial-of-service (resource exhaustion during rendering), misleading displays generated by rich, or potentially exploiting vulnerabilities if rich or the terminal emulator has parsing flaws.
  • Resource Exhaustion via Long Strings in Rich Rendering (Medium Severity): Extremely long strings, when processed by rich for rendering, can consume excessive resources, leading to slowdowns or denial-of-service specifically during rich's rendering process.
  • Cosmetic Output Manipulation via Rich (Low Severity): Users inject formatting codes that rich interprets to alter the intended appearance of output displayed by rich, causing confusion or misrepresentation within the rich output.

• Impact:

  • ANSI Escape Code Injection via Rich: Significantly reduces risk. Effective sanitization tailored for rich eliminates the ability to inject malicious formatting codes that rich would interpret.
  • Resource Exhaustion via Long Strings in Rich Rendering: Reduces risk if combined with input length limits applied before passing to rich. Sanitization alone might not prevent resource exhaustion if rich still processes very long, but safe, strings.
  • Cosmetic Output Manipulation via Rich: Eliminates or greatly reduces the ability to manipulate output appearance specifically through formatting codes that rich would render.

• Currently Implemented:

  • Location: Basic string escaping is implemented in the application's logging module before logging, which might indirectly sanitize some input that could be rendered by rich if logs are displayed in the terminal. However, this is not specifically designed for rich's rendering context.

• Missing Implementation:

  • Areas: Dedicated sanitization specifically for rich rendering is missing. User input displayed directly in the terminal interface using rich during interactive sessions is not sanitized with rich in mind. Markdown rendering of user-provided descriptions in help messages, when using rich for display, also lacks sanitization tailored for rich.

Mitigation Strategy: Control Rich Features Used with User Input

• Mitigation Strategy: Control Rich Features Used with User Input

• Description:

  1. Review Rich Feature Usage with User Data: Identify all instances in your application where rich features like rendering file links, clickable URLs, or Markdown are used to display user-controlled data.
  2. Assess Rich Feature Necessity for User Input: Determine if these specific rich features are genuinely necessary and beneficial when displaying user-provided content. If they are not essential for the user experience in these contexts, consider disabling them for user-provided content rendered by rich.
  3. Implement Rich Feature Restriction: If certain rich features are deemed necessary for user input display, implement controls within your rich usage to restrict their potential misuse:
     • Disable Unnecessary Rich Features: Configure rich's rendering context to explicitly disable features like file links or clickable URLs when rendering user input if they are not required. Consult rich's documentation for options to control feature rendering.
     • Parameter Validation for Rich Features: If specific rich features are used with user input, validate and sanitize the parameters passed to those rich features. For example, if using rich to render file links based on user input:
       • File Links in Rich: Validate that file paths provided by users, when used in rich's file link rendering, are within expected directories and do not allow access to sensitive system files. Implement path canonicalization before passing paths to rich's file link rendering.
       • URLs in Rich: If rich is used to render URLs from user input as clickable links, validate URL schemes (allow only http and https) before rich renders them. Potentially use a URL safelist to restrict allowed domains that rich will render as clickable links.
  4. Safe Markdown Rendering with Rich (if applicable): If you render user-provided content as Markdown using rich, and this is a necessary feature, investigate if rich offers any "safe mode" or options to limit potentially risky Markdown features during rendering. If not, consider using a separate Markdown sanitization library before passing the sanitized Markdown to rich for rendering.

• Threats Mitigated:

  • Malicious File Link Injection via Rich (Medium Severity): Users could inject file links that rich renders, potentially pointing to sensitive local files. While rich itself doesn't execute these links, if the application or users interact with these rendered links in an unsafe way, it could lead to information disclosure (threat is indirect via rich's rendering).
  • Malicious URL Injection via Rich (Medium Severity): Users could inject malicious URLs that rich renders as clickable links. If users click these links, it could lead to phishing attacks or redirection to harmful websites (threat is indirect, via user interaction with rich's output).
  • Markdown Injection via Rich (Low to Medium Severity): While rich's Markdown rendering is generally considered safer than browser-based rendering, malicious Markdown input, when rendered by rich, could still be used for cosmetic manipulation of the terminal output or, in less likely scenarios, to exploit potential parsing vulnerabilities within rich's Markdown rendering engine.

• Impact:

  • Malicious File Link Injection via Rich: Significantly reduces risk by preventing or validating file links rendered by rich, limiting potential for indirect information disclosure.
  • Malicious URL Injection via Rich: Reduces risk of phishing and malicious redirection by validating URL schemes and potentially using URL safelists before rich renders URLs as clickable links.
  • Markdown Injection via Rich: Reduces risk of cosmetic manipulation and potential parser vulnerabilities in rich's Markdown rendering by disabling or sanitizing Markdown features before rendering with rich.

• Currently Implemented:

  • Location: Clickable URLs are generally disabled in application logs displayed in the terminal, which are often rendered using rich.

• Missing Implementation:

  • Areas: File links are currently rendered by rich without validation in certain debug output sections. Markdown rendering in help messages, when displayed using rich, does not have specific feature restrictions or sanitization beyond general input sanitization, and no specific controls on rich's Markdown rendering features are in place.