attack-tree.md

Attack Tree Analysis for urfave/cli

Objective: To gain unauthorized access, execute arbitrary commands, cause denial of service, or exfiltrate sensitive information from the application by exploiting vulnerabilities in the application's CLI interface built with urfave/cli.

Attack Tree Visualization

[CRITICAL NODE] Compromise CLI Application [CRITICAL NODE] ├───[AND] [HIGH RISK PATH] Exploit Input Handling Vulnerabilities [HIGH RISK PATH] │ ├───[OR] [CRITICAL NODE] Command Injection [CRITICAL NODE] │ │ ├───[AND] Exploit Argument Parsing │ │ │ ├───[OR] Unsafe Argument Handling in Application Logic │ │ │ │ ├───[ACTION] [HIGH RISK PATH] Pass unsanitized arguments to shell commands (e.g., os/exec.Command) [HIGH RISK PATH] │ │ ├───[AND] Exploit Flag Parsing │ │ │ ├───[OR] Unsafe Flag Handling in Application Logic │ │ │ │ ├───[ACTION] [HIGH RISK PATH] Pass unsanitized flag values to shell commands [HIGH RISK PATH] │ │ ├───[AND] Exploit Subcommand Handling (if used) │ │ │ ├───[OR] Unsafe Subcommand Argument Handling │ │ │ │ ├───[ACTION] [HIGH RISK PATH] Pass subcommand arguments unsanitized to shell commands [HIGH RISK PATH] │ │ └───[ACTION] Leverage urfave/cli features for unintended command execution (e.g., misconfigured BashComplete) │ ├───[OR] [HIGH RISK PATH] Path Traversal [HIGH RISK PATH] │ │ ├───[AND] Exploit File Path Arguments │ │ │ ├───[ACTION] [HIGH RISK PATH] Provide relative paths in arguments to access files outside intended scope [HIGH RISK PATH] │ │ ├───[AND] Exploit Directory Path Arguments │ │ │ ├───[ACTION] [HIGH RISK PATH] Provide relative paths in arguments to access directories outside intended scope [HIGH RISK PATH] │ ├───[OR] [HIGH RISK PATH] Denial of Service (DoS) via Input [HIGH RISK PATH] │ │ ├───[AND] Resource Exhaustion │ │ │ ├───[OR] Memory Exhaustion │ │ │ │ ├───[ACTION] [HIGH RISK PATH] Provide excessively large input arguments/flags that consume memory during processing [HIGH RISK PATH] │ │ │ ├───[OR] CPU Exhaustion │ │ │ │ ├───[ACTION] [HIGH RISK PATH] Provide input that triggers computationally expensive operations (e.g., complex regex, infinite loops in processing) [HIGH RISK PATH] │ └───[OR] Information Disclosure via Input │ └───[AND] Verbose Error Messages │ └───[ACTION] Provide invalid input to trigger verbose error messages that reveal internal paths, configurations, or code snippets └───[AND] [HIGH RISK PATH] Exploit Application Logic Flaws Exposed via CLI [HIGH RISK PATH] ├───[OR] Business Logic Bypass │ └───[ACTION] [HIGH RISK PATH] Craft specific CLI commands and arguments to bypass intended application logic or access restricted functionalities [HIGH RISK PATH] └───[OR] Data Manipulation └───[ACTION] [HIGH RISK PATH] Use CLI commands to manipulate data in unintended ways, leading to data corruption or unauthorized modification [HIGH RISK PATH]

Attack Tree Path: [CRITICAL NODE] Command Injection

Attack Vector: Exploiting vulnerabilities to inject and execute arbitrary commands on the underlying operating system. This is a critical node because successful command injection can lead to complete system compromise.

• High-Risk Paths leading to Command Injection:
  • [HIGH RISK PATH] Pass unsanitized arguments to shell commands (e.g., os/exec.Command):
    • How it works: The application takes user-provided arguments (from CLI arguments, flags, or subcommand arguments) and directly passes them to shell commands without proper sanitization or escaping.
    • Example: If the application executes os/exec.Command("/bin/sh", "-c", "process_file " + userInput) and userInput is crafted as ; rm -rf /, the attacker can execute rm -rf / on the system.
    • Why High-Risk: High likelihood due to common programming errors, critical impact leading to full system compromise, low effort for exploitation, and intermediate skill level required.
  • [HIGH RISK PATH] Pass unsanitized flag values to shell commands:
    • How it works: Similar to argument injection, but the vulnerability lies in how flag values are handled when passed to shell commands.
    • Example: Application uses a flag --output-dir and executes os/exec.Command("/bin/sh", "-c", "create_output --dir=" + outputDirFlag). If outputDirFlag is ; malicious_command, it's injected.
    • Why High-Risk: Same risk profile as argument injection.
  • [HIGH RISK PATH] Pass subcommand arguments unsanitized to shell commands:
    • How it works: When using subcommands, arguments provided to subcommands can also be vulnerable if not sanitized before shell execution.
    • Example: app subcommand process --file <filename>. If <filename> is unsanitized and used in a shell command within the process subcommand logic.
    • Why High-Risk: Same risk profile as argument and flag injection.
  • [ACTION] Leverage urfave/cli features for unintended command execution (e.g., misconfigured BashComplete):
    • How it works: urfave/cli allows custom bash completion. If this feature is misconfigured or the completion script itself is vulnerable, it can be exploited to execute commands during tab completion.
    • Example: A malicious completion script could execute commands when a user tries to autocomplete a command or argument.
    • Why High-Risk: Lower likelihood due to less common usage of custom completion and misconfiguration requirement, but critical impact if exploited.

Attack Tree Path: [HIGH RISK PATH] Path Traversal

Attack Vector: Exploiting vulnerabilities to access files or directories outside of the intended scope by manipulating file or directory paths provided as input.

• High-Risk Paths leading to Path Traversal:
  • [HIGH RISK PATH] Provide relative paths in arguments to access files outside intended scope:
    • How it works: The application accepts file paths as arguments and uses them to access files. If relative paths like ../../sensitive_file are not properly validated and sanitized, attackers can traverse up the directory structure to access sensitive files.
    • Example: app process --input ../../etc/passwd. If the application reads the file specified by --input without path validation, it can read /etc/passwd.
    • Why High-Risk: Medium likelihood due to common oversight in path handling, medium/high impact leading to data breaches, low effort, and beginner skill level.
  • [HIGH RISK PATH] Provide relative paths in arguments to access directories outside intended scope:
    • How it works: Similar to file path traversal, but targeting directories. Attackers can access or list contents of directories outside the intended scope.
    • Example: app list --dir ../../sensitive_dir. If the application lists files in the directory specified by --dir without validation, it can list contents of sensitive_dir.
    • Why High-Risk: Similar risk profile to file path traversal.

Attack Tree Path: [HIGH RISK PATH] Denial of Service (DoS) via Input

Attack Vector: Exploiting vulnerabilities to cause a denial of service by providing malicious input that exhausts application resources or crashes the application.

• High-Risk Paths leading to DoS:
  • [HIGH RISK PATH] Provide excessively large input arguments/flags that consume memory during processing:
    • How it works: Providing extremely large arguments or flag values can cause the application to allocate excessive memory, leading to memory exhaustion and DoS.
    • Example: app process --data <very_large_string>. If the application loads the --data string into memory without limits, it can crash due to OOM.
    • Why High-Risk: Medium likelihood, medium impact (application DoS), low effort, beginner skill level.
  • [HIGH RISK PATH] Provide input that triggers computationally expensive operations (e.g., complex regex, infinite loops in processing):
    • How it works: Crafting input that triggers computationally intensive operations within the application logic can lead to CPU exhaustion and DoS.
    • Example: If the application uses a regex to validate input, providing a specially crafted string that causes catastrophic backtracking in the regex engine can lead to CPU spikes.
    • Why High-Risk: Medium likelihood, medium impact (application DoS), low effort, beginner/intermediate skill level.

Attack Tree Path: [HIGH RISK PATH] Exploit Application Logic Flaws Exposed via CLI

Attack Vector: Exploiting flaws in the application's business logic that are accessible or exposed through the CLI interface.

• High-Risk Paths related to Application Logic Flaws:
  • [HIGH RISK PATH] Craft specific CLI commands and arguments to bypass intended application logic or access restricted functionalities:
    • How it works: Attackers analyze the CLI commands and arguments to find combinations that bypass intended access controls, business rules, or workflows within the application.
    • Example: A CLI might have commands for "user" and "admin". By carefully crafting commands or arguments, a regular user might be able to access admin functionalities.
    • Why High-Risk: Medium likelihood (depends on application complexity), medium/high impact (unauthorized access, data manipulation), medium effort, intermediate skill level.
  • [HIGH RISK PATH] Use CLI commands to manipulate data in unintended ways, leading to data corruption or unauthorized modification:
    • How it works: Attackers use CLI commands in sequences or with specific arguments to manipulate data in ways not intended by the application developers, leading to data corruption, integrity issues, or unauthorized modifications.
    • Example: A CLI might have commands to "create" and "update" data. By using these commands in a specific order or with crafted data, an attacker might be able to corrupt data relationships or modify data they shouldn't be able to.
    • Why High-Risk: Medium likelihood (depends on application logic and data handling), medium/high impact (data integrity issues, financial loss), medium effort, intermediate skill level.