Ticket #39915: 39915-email-unsafe.diff

src/wp-includes/ms-functions.php

@@ -354 +354 @@
 
         $is_email_address_unsafe = false;
 
-        if ( $banned_names && is_array( $banned_names ) ) {
+        if ( $banned_names && is_array( $banned_names ) && false !== strpos( $user_email, '@', 1 ) ) {
                 $banned_names = array_map( 'strtolower', $banned_names );
                 $normalized_email = strtolower( $user_email );