Attack Surface Analysis for burntsushi/ripgrep

Attack Surface: Command Injection via Unsanitized Search Patterns

Description: Attackers inject malicious commands by exploiting insufficient sanitization of user-provided search patterns that are directly passed to ripgrep.
Ripgrep Contribution: ripgrep executes commands constructed by the application, including user-provided search patterns. Lack of sanitization in the application directly leads to this vulnerability when using ripgrep.
Example: An application constructs a command like ripgrep "{user_input}" /path/to/search. If a user inputs ; rm -rf /, and the application executes this command via a shell without proper sanitization, it can lead to arbitrary command execution.
Impact: Arbitrary command execution on the server, potentially leading to data breach, system compromise, denial of service, or privilege escalation.
Risk Severity: Critical
Mitigation Strategies:
- Strict Input Sanitization: Thoroughly sanitize and validate user-provided search patterns before passing them to ripgrep. Use allowlists for permitted characters and escape shell metacharacters if shell execution is used.
- Parameterization/Prepared Statements (if possible): Utilize parameterized command execution methods if available in your programming environment to separate commands from user-provided data.
- Principle of Least Privilege: Run ripgrep with minimal necessary privileges to limit the impact of successful command injection.
- Avoid Shell Execution: If possible, use libraries that allow direct process execution without invoking a shell to reduce shell injection risks.

Attack Surface: Path Traversal via Unsanitized File Paths/Globs

Description: Attackers gain unauthorized access to files or directories outside the intended scope by manipulating file paths or glob patterns passed to ripgrep.
Ripgrep Contribution: ripgrep operates directly on file paths and glob patterns provided by the application. If the application doesn't validate these inputs, attackers can instruct ripgrep to access unintended areas.
Example: An application intends to allow searching within /var/app/data. If it naively uses user input to construct the search path, a user could input ../../../../etc/passwd to make ripgrep attempt to access the password file, bypassing the intended directory restriction.
Impact: Unauthorized access to sensitive files, information disclosure, potential for further exploitation if sensitive configuration files are accessed.
Risk Severity: High
Mitigation Strategies:
- Input Validation and Whitelisting: Strictly validate user-provided file paths and glob patterns. Use whitelists to define allowed base directories and file extensions.
- Path Canonicalization: Canonicalize paths to resolve symbolic links and relative paths before passing them to ripgrep. Compare the canonicalized path against allowed, canonicalized base paths.
- Restrict Search Scope: Limit the directories and file types that ripgrep is allowed to access based on application logic and user permissions.

Attack Surface: Regular Expression Denial of Service (ReDoS)

Description: Attackers craft malicious regular expressions that cause ripgrep's regex engine to consume excessive CPU and memory, leading to denial of service.
Ripgrep Contribution: ripgrep's core functionality relies on regular expression matching. Vulnerability to ReDoS arises when ripgrep processes complex or maliciously crafted regex patterns, especially if user-provided.
Example: A user provides a regex like (a+)+$. When ripgrep attempts to match this against a long string of 'a's followed by a 'b', it can trigger exponential backtracking in the regex engine, leading to CPU exhaustion and application slowdown or freeze.
Impact: Application denial of service, performance degradation, resource exhaustion, potentially impacting other services on the same system.
Risk Severity: High
Mitigation Strategies:
- Regex Complexity Limits: Implement limits on the complexity of user-provided regular expressions. This can include character limits, nesting depth restrictions, or using static analysis to detect potentially problematic patterns.
- Regex Timeout: Set a timeout for regex matching operations within ripgrep. If a match takes longer than the timeout, terminate the operation to prevent resource exhaustion.
- Safe Regex Libraries/Engines: Consider using regex libraries or engines that are designed to be more resistant to ReDoS vulnerabilities or have built-in safeguards.
- Predefined Regex Options: Offer users a selection of predefined, safe regex options instead of allowing arbitrary regex input, where feasible for the application's functionality.