Crovly – Proof of Work Captcha & Spam Protection
Crovly is a privacy-first captcha service powered by Proof of Work. Unlike traditional captchas that rely on image puzzles (easily solved by AI) or invasive tracking, Crovly makes the visitor’s browser do computational work to prove it’s not a bot. How it works: Your visitor’s browser solves a small cryptographic puzzle (Proof of Work) Browser fingerprint and environment signals are collected (as a hash — no personal data stored) Behavioral analysis detects automated patterns (mouse, keyboard, scroll) A composite score determines if the visitor is human Key features: Privacy-friendly — No cookies, no cross-site tracking No image puzzles — Invisible to legitimate users Resistant to AI vision attacks — Proof of Work cannot be solved by image recognition IP binding — Tokens are bound to the solver’s IP address Adaptive difficulty — Suspicious visitors receive harder challenges 22+ integrations — Works with major WordPress form plugins Lightweight — Widget is under 25KB gzipped, zero dependencies, 42 languages Supported integrations: WordPress login, registration, lost password, comments WooCommerce (checkout, login, register, lost password, pay for order) Contact Form 7 WPForms Gravity Forms Elementor Pro Forms Ninja Forms Fluent Forms Formidable Forms Forminator Jetpack Contact Form Divi (contact form, login) BuddyPress (registration, activity) bbPress (topics, replies) Ultimate Member (login, register, password reset) MemberPress (checkout, login) Paid Memberships Pro Easy Digital Downloads Mailchimp for WordPress GiveWP wpDiscuz wpForo WordPress Multisite signup Shortcode & PHP support: Use [crovly] shortcode in any page or post, or call crovly_render() and crovly_verify() in your theme templates. External services This plugin relies on the Crovly captcha service to function. It connects to two external endpoints: 1. Crovly Widget CDN (get.crovly.com) The plugin loads the JavaScript widget from https://get.crovly.com/widget.js on any page that contains a protected form. The widget runs Proof of Work in the visitor’s browser and collects a hashed browser fingerprint. When: Loaded on frontend pages that display a protected form (login, register, comment, checkout, etc.) What is sent: Standard HTTP request headers (IP address, user agent). No personal data. Terms of Service: https://crovly.com/terms Privacy Policy: https://crovly.com/privacy 2. Crovly Verification API (api.crovly.com) When a visitor submits a protected form, the plugin sends the generated captcha token to https://api.crovly.com/verify-token for server-side verification. When: On form submission of any form protected by Crovly. What is sent: The captcha token (opaque string), the visitor’s IP address (for IP binding), and your Secret Key (for authentication). What is received: A success/failure response indicating whether the token is valid. Terms of Service: https://crovly.com/terms Privacy Policy: https://crovly.com/privacy Both services are operated by Crovly. No data is shared with third parties. The plugin does not set cookies or track visitors across sites.
KillBot
The KillBot plugin for WordPress uses the external KillBot service to protect websites from bots and automated traffic. What is this service, and what is it used for? KillBot is an anti-bot system that analyzes traffic, detects bots, and can either block them or present a CAPTCHA. The plugin interacts with the KillBot service to check users for signs of automated behavior and detect the use of proxies or VPNs. What data is sent and when? The plugin sends the following data to the KillBot server upon each new visit session: – The window.navigator object – The window.screen object – The window object (excluding string-based parameter values) Important: KillBot does not receive any personal user data, such as names, email addresses, or account identifiers. Links to Terms of Service and Privacy Policy KillBot Terms of Service: https://my.kill-bot.net/node/7 KillBot Privacy Policy: https://my.kill-bot.net/node/29
