diff --git a/phpBB/includes/acp/acp_board.php b/phpBB/includes/acp/acp_board.php
index 5b37bb5c57..e348c769bd 100644
--- a/phpBB/includes/acp/acp_board.php
+++ b/phpBB/includes/acp/acp_board.php
@@ -125,6 +125,7 @@ class acp_board
 				$avatar_vars = array();
 				foreach ($avatar_drivers as $current_driver)
 				{
+					/** @var \phpbb\avatar\driver\driver_interface $driver */
 					$driver = $phpbb_avatar_manager->get_driver($current_driver, false);
 
 					/*
@@ -733,7 +734,7 @@ class acp_board
 			$template->assign_block_vars('options', array(
 				'KEY'			=> $config_key,
 				'TITLE'			=> (isset($user->lang[$vars['lang']])) ? $user->lang[$vars['lang']] : $vars['lang'],
-				'S_EXPLAIN'		=> $vars['explain'],
+				'S_EXPLAIN'		=> $vars['explain'] && !empty($l_explain),
 				'TITLE_EXPLAIN'	=> $l_explain,
 				'CONTENT'		=> $content,
 				)
diff --git a/phpBB/language/en/acp/board.php b/phpBB/language/en/acp/board.php
index eb53ac0370..9b45ffa45b 100644
--- a/phpBB/language/en/acp/board.php
+++ b/phpBB/language/en/acp/board.php
@@ -111,9 +111,9 @@ $lang = array_merge($lang, array(
 	'ALLOW_GRAVATAR'				=> 'Enable gravatar avatars',
 	'ALLOW_LOCAL'					=> 'Enable gallery avatars',
 	'ALLOW_REMOTE'					=> 'Enable remote avatars',
-	'ALLOW_REMOTE_EXPLAIN'			=> 'Avatars linked to from another website.',
+	'ALLOW_REMOTE_EXPLAIN'			=> 'Avatars linked to from another website.<br><em><strong class="error">Warning:</strong> Enabling this feature might allow users to check for the existence of files and services that are only accessible on the local network.</em>',
 	'ALLOW_REMOTE_UPLOAD'			=> 'Enable remote avatar uploading',
-	'ALLOW_REMOTE_UPLOAD_EXPLAIN'	=> 'Allow uploading of avatars from another website.',
+	'ALLOW_REMOTE_UPLOAD_EXPLAIN'	=> 'Allow uploading of avatars from another website.<br><em><strong class="error">Warning:</strong> Enabling this feature might allow users to check for the existence of files and services that are only accessible on the local network.</em>',
 	'ALLOW_UPLOAD'					=> 'Enable avatar uploading',
 	'AVATAR_GALLERY_PATH'			=> 'Avatar gallery path',
 	'AVATAR_GALLERY_PATH_EXPLAIN'	=> 'Path under your phpBB root directory for pre-loaded images, e.g. <samp>images/avatars/gallery</samp>.<br>Double dots like <samp>../</samp> will be stripped from the path for security reasons.',
diff --git a/phpBB/phpbb/avatar/manager.php b/phpBB/phpbb/avatar/manager.php
index 6d9604db04..a909a91042 100644
--- a/phpBB/phpbb/avatar/manager.php
+++ b/phpBB/phpbb/avatar/manager.php
@@ -271,7 +271,7 @@ class manager
 		$config_name = $driver->get_config_name();
 
 		return array(
-			'allow_avatar_' . $config_name	=> array('lang' => 'ALLOW_' . strtoupper(str_replace('\\', '_', $config_name)),		'validate' => 'bool',	'type' => 'radio:yes_no', 'explain' => false),
+			'allow_avatar_' . $config_name	=> array('lang' => 'ALLOW_' . strtoupper(str_replace('\\', '_', $config_name)),		'validate' => 'bool',	'type' => 'radio:yes_no', 'explain' => true),
 		);
 	}
 
diff --git a/phpBB/phpbb/db/migration/data/v32x/disable_remote_avatar.php b/phpBB/phpbb/db/migration/data/v32x/disable_remote_avatar.php
new file mode 100644
index 0000000000..b08833fad4
--- /dev/null
+++ b/phpBB/phpbb/db/migration/data/v32x/disable_remote_avatar.php
@@ -0,0 +1,34 @@
+<?php
+/**
+ *
+ * This file is part of the phpBB Forum Software package.
+ *
+ * @copyright (c) phpBB Limited <https://www.phpbb.com>
+ * @license GNU General Public License, version 2 (GPL-2.0)
+ *
+ * For full copyright and license information, please see
+ * the docs/CREDITS.txt file.
+ *
+ */
+
+namespace phpbb\db\migration\data\v32x;
+
+use phpbb\db\migration\migration;
+
+class disable_remote_avatar extends migration
+{
+	static public function depends_on()
+	{
+		return array(
+			'\phpbb\db\migration\data\v32x\v325',
+		);
+	}
+
+	public function update_data()
+	{
+		return array(
+			array('config.update', array('allow_avatar_remote', '0')),
+			array('config.update', array('allow_avatar_remote_upload', '0')),
+		);
+	}
+}