Title: PHP warnings: Undefined HTTP_HOST / REQUEST_METHOD in Brevo plugin files
Last modified: May 16, 2026

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# PHP warnings: Undefined HTTP_HOST / REQUEST_METHOD in Brevo plugin files

 *  Resolved [jafarsadiqu](https://wordpress.org/support/users/jafarsadiqu/)
 * (@jafarsadiqu)
 * [3 weeks, 2 days ago](https://wordpress.org/support/topic/php-warnings-undefined-http_host-request_method-in-brevo-plugin-files/)
 * Hi,
 * We are seeing repeated PHP warnings from the Brevo/Mailin plugin in our server
   logs.
 * Plugin/files:
   wp-content/plugins/mailin/inc/sendinblue.phpwp-content/plugins/
   mailin/inc/push-api.php
 * Exact warnings:
   PHP Warning: Undefined array key “HTTP_HOST” in /wp-content/plugins/
   mailin/inc/sendinblue.php
 * PHP Warning: Undefined array key “REQUEST_METHOD” in /wp-content/plugins/mailin/
   inc/push-api.php
 * Environment:
    - WordPress / WooCommerce site
    - PHP 8.2
    - Standard WordPress/WooCommerce site, not headless
 * Could you please confirm if there is an updated version or recommended patch 
   for this issue?

Viewing 1 replies (of 1 total)

 *  Plugin Support [shreyachawla](https://wordpress.org/support/users/shreyachawla/)
 * (@shreyachawla)
 * [2 weeks, 6 days ago](https://wordpress.org/support/topic/php-warnings-undefined-http_host-request_method-in-brevo-plugin-files/#post-18911755)
 * Hi,
 * Thank you for reaching out and for providing such detailed information about 
   the warnings you’re encountering.
 * **What’s happening**
 * The warnings you’re seeing are related to PHP 8.x compatibility. Starting with
   PHP 8.0, accessing an undefined array key generates a `Warning` rather than silently
   returning `null` as it did in PHP 7.x. In your case, the plugin is accessing `
   $_SERVER['HTTP_HOST']` and `$_SERVER['REQUEST_METHOD']` without first checking
   whether those keys exist, which can happen in certain contexts (e.g., CLI/cron
   executions where HTTP server variables are not set).
 * The good news is these are **non-fatal warnings** and do not affect the functionality
   of your site for regular web traffic.
 * **Recommended action: Update the plugin**
 * We recommend updating to the latest available version of the Brevo plugin (**
   v3.3.4**), which includes PHP compatibility fixes. You can do this directly from
   your WordPress dashboard.
 * Version 3.2.5 specifically included “technical improvements related to PHP 8 
   warnings,” and subsequent versions have continued PHP compatibility improvements.
 * **If the warnings persist after updating**
 * If you continue to see these specific warnings after updating to v3.3.4, a temporary
   workaround is to suppress PHP warnings at the log level, or to configure your
   PHP error reporting to exclude `E_WARNING` for this plugin path. However, we 
   would strongly recommend reporting the issue so it can be reviewed and patched
   properly.
 * If the warnings remain present on the latest version, please let us know and 
   we will guide you further.
 * We apologize for any inconvenience this has caused and appreciate you flagging
   it so clearly.
 * Best regards,

Viewing 1 replies (of 1 total)

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 * ![](https://ps.w.org/mailin/assets/icon-256x256.png?rev=2993173)
 * [Brevo - Email, SMS, Web Push, Chat, and more.](https://wordpress.org/plugins/mailin/)
 * [Frequently Asked Questions](https://wordpress.org/plugins/mailin/#faq)
 * [Support Threads](https://wordpress.org/support/plugin/mailin/)
 * [Active Topics](https://wordpress.org/support/plugin/mailin/active/)
 * [Unresolved Topics](https://wordpress.org/support/plugin/mailin/unresolved/)
 * [Reviews](https://wordpress.org/support/plugin/mailin/reviews/)

 * 1 reply
 * 2 participants
 * Last reply from: [shreyachawla](https://wordpress.org/support/users/shreyachawla/)
 * Last activity: [2 weeks, 6 days ago](https://wordpress.org/support/topic/php-warnings-undefined-http_host-request_method-in-brevo-plugin-files/#post-18911755)
 * Status: resolved