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Attack Surface Analysis for burntsushi/ripgrep

Attack Surface: Uncontrolled File System Access

  • Description: ripgrep searches the file system based on provided paths. If these paths are not properly validated, an attacker can access unintended files, potentially outside the application's intended scope.
  • How ripgrep contributes: ripgrep's core function is file system searching; its power becomes a liability without strict input validation and access control.
  • Example: An application allows users to specify a directory. An attacker provides ../../../../etc/passwd (or a similar path traversal) to read system files.
  • Impact: Information disclosure (sensitive data, configuration files, source code). Potentially, system compromise if combined with other vulnerabilities.
  • Risk Severity: Critical
  • Mitigation Strategies:
    • Whitelist: Only allow access to specific, pre-approved directories. Never construct paths by directly concatenating user input.
    • Sanitize: Thoroughly validate and sanitize user-provided paths, removing any .., ., or other potentially dangerous characters. Use a robust path normalization library.
    • Chroot/Containerization: Run ripgrep in a restricted environment (chroot jail or container) to limit its file system access.
    • Least Privilege: Run ripgrep with the lowest possible user privileges.

Attack Surface: Regular Expression Denial of Service (ReDoS)

  • Description: ripgrep uses regular expressions for pattern matching. Maliciously crafted regular expressions can cause excessive processing time (catastrophic backtracking), leading to a denial of service.
  • How ripgrep contributes: ripgrep's reliance on regular expressions for its core functionality creates this vulnerability.
  • Example: An attacker provides a regex like (a+)+$ against a long string of "a" characters, causing ripgrep to consume excessive CPU and become unresponsive.
  • Impact: Denial of Service (DoS) – the application becomes unresponsive or crashes.
  • Risk Severity: High
  • Mitigation Strategies:
    • Predefined Patterns: Strongly prefer allowing users to select from a predefined list of safe search patterns, rather than allowing arbitrary regular expressions.
    • Regex Sanitization: If user-provided regex is absolutely unavoidable, use a regex validator/sanitizer to reject potentially dangerous patterns. This is difficult to do perfectly, so prioritize the previous mitigation.
    • Timeouts: Implement strict timeouts for all ripgrep executions.
    • Simpler Matching: If full regex power isn't essential, use simpler string matching (e.g., fgrep functionality or ripgrep's literal matching options).
    • Resource Limits: Limit CPU and memory usage for ripgrep processes (e.g., using ulimit or container resource limits).

Attack Surface: Resource Exhaustion (Non-ReDoS)

  • Description: ripgrep can be forced to consume excessive resources (memory, CPU, file handles) even without malicious regex, by searching large files, many small files, or deeply nested directories.
  • How ripgrep contributes: ripgrep's speed and efficiency can be exploited if its resource usage is not constrained.
  • Example: An attacker directs ripgrep to a directory with millions of tiny files, a very large log file, or a deeply nested directory structure (potentially involving symbolic link loops).
  • Impact: Denial of Service (DoS) – the application or the entire system becomes unresponsive or crashes.
  • Risk Severity: High
  • Mitigation Strategies:
    • -maxdepth: Always use the -maxdepth option with a reasonable, application-specific limit to control recursion depth.
    • -max-filesize: Use -max-filesize to limit the size of files that ripgrep will process.
    • Timeouts: Implement strict timeouts for all ripgrep executions.
    • File Type/Directory Restrictions: If feasible, restrict ripgrep to specific file types or directories known to contain reasonably sized files.
    • Rate Limiting/Queuing: Implement rate limiting or queuing for search requests to prevent abuse.
    • Limit number of files: Limit the number of files that can be searched.

Attack Surface: Binary Planting (via PATH)

  • Description: An attacker places a malicious executable named rg in a directory earlier in the PATH environment variable than the real ripgrep executable. When the application tries to run ripgrep, it executes the attacker's code instead.
  • How ripgrep contributes: While a general attack, ripgrep's frequent use as a subprocess makes it a likely target. The application calls ripgrep, making this relevant.
  • Example: An attacker places a malicious rg executable in /tmp, and the application's PATH includes /tmp before the directory containing the legitimate ripgrep.
  • Impact: Arbitrary code execution with the privileges of the application. This is a very serious compromise.
  • Risk Severity: Critical
  • Mitigation Strategies:
    • Absolute Path: Always use the absolute path to the ripgrep executable when launching it as a subprocess. This is the most reliable mitigation.
    • Controlled PATH: Carefully control the PATH environment variable, ensuring it only includes trusted directories. Never include user-writable directories like /tmp in the PATH.