🛡️ CF7 Spam Blocker Plugin

This plugin blocks spam submissions in Contact Form 7 (CF7) forms using regex and keyword-based filtering, with detailed logging.

Known Issue: Form in not being submitted with CloudFlare. Keeps rotating. Need to fix.

✅ Key Functionalities

1. Regex-based Spam Filtering

• Scans all CF7 form fields for suspicious content using predefined regex patterns.
• Blocks fields containing:
  • Email addresses in non-email fields
  • Links (e.g., http://, https://, www.)
  • HTML tags
  • Foreign alphabets (e.g., Cyrillic, Japanese, Arabic)
  • Encoded characters or emoji
  • Phone numbers and formatted numbers
• Patterns are defined in a PHP array named $regex_checks.

2. Keyword-based Spam Filtering

• Blocks messages containing blacklisted keywords.

• Keywords are stored in the WordPress options table under the key:

  cf7_spam_blocked_keywords

• Supports:

  • Case-insensitive matching
  • Trimming for extra whitespace

• You can update the keyword list programmatically or via the database.

3. Spam Logging

• Every blocked submission is logged to a file:

  wp-content/uploads/cf7-spam-logs/spam-log.txt

• Each entry includes:

  • Timestamp
  • Field name
  • Block type (Regex / Keyword)
  • Matched pattern or word
  • IP address

• Log entry format:

  [YYYY-MM-DD HH:MM:SS] Blocked in field "field_name" | Type: Regex | Match: http | IP: 123.45.67.89

4. Admin Feedback

• Users receive the following generic error if their message is blocked:

    There was an error trying to send your message. Please try again later.

• No spam details are disclosed to avoid filter circumvention.

5. Plugin Activation Hook

• On plugin activation:
• Initializes an empty array in the cf7_spam_blocked_keywords option if not already set.
• Ensures the logging directory cf7-spam-logs is created with write permissions.

🧠 Internal Mechanism

• Hooks into:

wpcf7_before_send_mail

• For each submission:

1. Iterates over all submitted fields.
2. Runs regex filters first.
3. If regex passes, runs keyword checks.
4. If any match is found:
   • Logs the attempt
   • Returns a generic error
   • Prevents email from sending

🧩 Possible Enhancements

• WP Admin settings page to manage keywords.
• Auto-purge or rotate logs.