HSArticle Math CAPTCHA for Forms
| 开发者 | hsarticle |
|---|---|
| 更新时间 | 2026年7月11日 23:07 |
| PHP版本: | 7.4 及以上 |
| WordPress版本: | 7.0 |
| 版权: | GPLv2 or later |
| 版权网址: | 版权信息 |
详情介绍:
- Math CAPTCHA — addition, subtraction, multiplication with sensible number ranges
- Two display modes: distorted canvas image (bot-resistant) or plain text (accessible)
- Server-side validation — answer stored in PHP session with HMAC signature, never exposed to the client
- Honeypot field — silent bot trap alongside the math challenge
- Rate limiting — blocks IPs after 10 failed attempts per 10 minutes
- Refresh button — generate a new question without reloading
- WPForms auto inject — protect any WPForms (free or pro) without adding a shortcode
- Registered as a CF7 form tag — no unknown tag warnings in the CF7 editor
- Session only starts on pages that actually contain a form — no impact on page caching elsewhere
- Clean admin page under its own menu — not buried under Settings
- Contact Form 7
- WPForms (Free and Pro)
- Any HTML form via the [hs_mcf_captcha] shortcode
安装:
- Upload the plugin folder to /wp-content/plugins/
- Activate via the Plugins menu
- Go to Math CAPTCHA in the left admin menu
- Choose display mode and configure WPForms auto inject if needed
常见问题:
Does this need an API key?
No. Fully self-hosted, no external services.
Does it work with WPForms free?
Yes. Use the auto inject option in plugin settings — no HTML field required.
Is it GDPR friendly?
Yes. No data is sent to third parties. The answer is stored in a server-side PHP session only and cleared immediately after validation.
Does it affect page caching?
The plugin only starts a PHP session on pages that actually render a form. Pages without a form are not affected. For pages with forms, you should exclude them from full-page caching in your caching plugin (WP Rocket, W3 Total Cache, LiteSpeed Cache, etc.) to ensure the CAPTCHA field ID matches the session. This is standard practice for any form page.
What if PHP sessions are disabled on my host?
Most shared hosts have PHP sessions enabled. If CAPTCHA validation always fails, ask your host to confirm sessions are available. Some managed hosts (such as WP Engine) restrict native PHP sessions — contact their support to enable session handling.
Can bots bypass this?
Sophisticated bots that render JavaScript and solve math can bypass any math CAPTCHA. This plugin stops the vast majority of spam bots which are simple automated form fillers. Additional layers (honeypot field and IP rate limiting) are built in. For high-security forms consider combining with Cloudflare Turnstile or hCaptcha.
更新日志:
- Initial release