Description: While urfave/cli itself doesn't execute commands, it parses user input. If the application then takes this parsed input (from any flag type) and uses it unsanitized in a function like os/exec.Command, syscall.Exec, or similar, an attacker can inject shell metacharacters to execute arbitrary commands. The attacker's input is processed by urfave/cli, and the result of that processing is misused.
Impact:
* Complete system compromise.
* Data exfiltration.
* Malware installation.
* Lateral movement.
Affected urfave/cli Component: All flag types (StringFlag, IntFlag, etc.) and arguments. The vulnerability is in how the application uses the data after urfave/cli has parsed it, but the input originates from the CLI and is handled by urfave/cli.
Risk Severity: Critical
Mitigation Strategies:
* Avoid os/exec with User Input: Prioritize Go's standard library for system interactions (e.g., os.OpenFile, net/http).
* Safe Command Execution Library: If shell commands are unavoidable, use a library designed for secure command execution, handling escaping automatically.
* Strict Input Validation/Whitelisting: Implement rigorous input validation, preferably using whitelists. Reject non-conforming input.
* Principle of Least Privilege: Run the application with minimal necessary privileges.
Description: Similar to command injection, this isn't a direct urfave/cli flaw, but a misuse of its output. An attacker provides a malicious path (e.g., ../../etc/passwd) to a StringFlag (or any flag used for file paths). If the application uses this parsed value directly in file operations (e.g., os.Open, ioutil.ReadFile) without sanitization, the attacker can access arbitrary files. urfave/cli parses the malicious input, and the application then misuses the result.
Impact:
* Reading sensitive files (configuration, keys).
* Overwriting critical system files (DoS, code execution).
* Information disclosure (file system structure).
Affected urfave/cli Component: Any flag type (usually StringFlag) used to construct file paths. The vulnerability is in the application's use of the parsed flag value, but the input is processed by urfave/cli.
Risk Severity: High
Mitigation Strategies:
* filepath.Clean: Always use filepath.Clean to normalize the user-provided path.
* Base Directory Check: After cleaning, verify the path remains within an allowed base directory (e.g., using strings.HasPrefix).
* Whitelist Allowed Files/Directories: If possible, use a whitelist to restrict access to specific files or directories.
* Avoid User-Provided Paths: If feasible, avoid using user-provided paths entirely; use configuration files or other mechanisms.
Description: The application uses urfave/cli's Before action (a function executed before a command's main action) to perform privileged operations without adequate authorization checks. Because Before actions run before the main command logic, they can be exploited to bypass intended security controls. This is a direct misuse of a urfave/cli feature.
Impact:
* Bypass of security checks.
* Unauthorized access to resources.
* Elevation of privilege.
Affected urfave/cli Component: The Before field of cli.Command and cli.App. The vulnerability lies in the logic within the Before action itself, making it a direct urfave/cli concern.
Risk Severity: High
Mitigation Strategies:
* Careful Design of Before Actions: Avoid performing privileged operations in Before actions unless absolutely necessary and with robust authorization checks.
* Input Validation: Validate any input used within the Before action, even if it seems to come from a trusted source.
* Principle of Least Privilege: Ensure the Before action itself operates with the minimum necessary privileges.