attack-tree.md

Attack Tree Analysis for inconshreveable/ngrok

Objective: Gain Unauthorized Access/Data Manipulation via ngrok

Attack Tree Visualization

                                      Gain Unauthorized Access/Data Manipulation via ngrok
                                                      |
        -------------------------------------------------------------------------
        |
  Abuse ngrok Features/Configuration
        |
  ---------------------
  |                   |
Tunnel Hijacking   Expose Sensitive Info
        |                   |
  ---------------     ---------------
  |             |     |             |
  1.2           2.1 [CRITICAL]
Predict      Unintended
Tunnel       Exposure
Names        (e.g.,
             .env files,
             logs)

(L/H/VL/S/M)   (M/VH/VL/S/E)

Attack Tree Path: 1. Abuse ngrok Features/Configuration

• 1. Abuse ngrok Features/Configuration: Exploiting intended features or misconfigurations of ngrok itself. This is the top-level category for the high-risk paths.

Attack Tree Path: Tunnel Hijacking

*   **Tunnel Hijacking:** A general category of attacks where the attacker gains unauthorized access to the ngrok tunnel.

Attack Tree Path: 1.2 Predict Tunnel Names

    *   **1.2 Predict Tunnel Names:**
        *   **Description:** If predictable tunnel names are used (e.g., the default random names *without* an authtoken), an attacker could potentially guess the tunnel URL and access the exposed application. The risk is significantly reduced by using authtokens.
        *   **Likelihood:** Low (With authtokens; High without)
        *   **Impact:** High (Full access to the exposed application)
        *   **Effort:** Very Low (Brute-forcing or guessing)
        *   **Skill Level:** Script Kiddie
        *   **Detection Difficulty:** Medium (Requires monitoring connection attempts; easier with intrusion detection)
        *   **Actionable Insights:**
            *   **Mandatory:** Use `ngrok` authtokens. This is the primary mitigation.
            *   Consider using custom subdomains (paid feature) for added obscurity.
            *   Monitor `ngrok` logs for unusual connection attempts.

Attack Tree Path: Expose Sensitive Info

*   **Expose Sensitive Info:** A category of attacks where sensitive information is unintentionally made accessible through the ngrok tunnel.

Attack Tree Path: 2.1 Unintended Exposure (e.g., .env files, logs) [CRITICAL]

    *   **2.1 Unintended Exposure (e.g., .env files, logs) `[CRITICAL]`:**
        *   **Description:** Developers might accidentally expose sensitive information (API keys, database credentials, `ngrok` authtokens) through the tunnel. This is often due to misconfigured web servers that serve files they shouldn't (like `.env` files, configuration files, or log files containing sensitive data). This is the *most critical* vulnerability to address.
        *   **Likelihood:** Medium (Common misconfiguration)
        *   **Impact:** Very High (Exposure of sensitive credentials, leading to complete compromise)
        *   **Effort:** Very Low (Simply browsing to common file paths)
        *   **Skill Level:** Script Kiddie
        *   **Detection Difficulty:** Easy (If the attacker accesses the files, it's immediately obvious; the key is to *prevent* access)
        *   **Actionable Insights:**
            *   **Crucial:** Configure your web server (Apache, Nginx, etc.) *correctly* to *deny* access to sensitive files and directories. Use `.htaccess` (Apache) or server block configurations (Nginx) to explicitly block access to `.env`, log files, and any other files that should not be publicly accessible. This is the *highest priority* mitigation.
            *   Review your web server's document root and ensure it only contains the necessary files for your application.
            *   Use a web application firewall (WAF) to add an extra layer of protection and block requests for known sensitive file paths.
            *   Regularly audit your application and server configuration for potential exposure points.