Fix several vulnerabilities (#13927)

* Escape HTML in the location field of a calendar event post

- This allowed script tags to be interpreted in the post display of an event.

* Add form security token check to /admin/phpinfo module

- This prevents basic XSS attacks against /admin/phpinfo

* Add form security token check to /babel module

- This prevents basic XSS attacks against /babel

* Prevent pass-through for attachments

- This addresses a straightforward Reflected XSS vulnerability if a malicious HTML/Javascript file is attached to a post through upload

* Prevent overwriting cid on event edit

- This allowed to share an event as any other user after zeroing the cid field of an existing event

src/Model/Event.php

@@ -925,9 +925,6 @@ class Event
 			$end_short   = '';
 		}
 
-		// Format the event location.
-		$location = self::locationToArray($item['event-location']);
-
 		// Construct the profile link (magic-auth).
 		$author       = [
 			'uid'     => 0,
@@ -964,7 +961,7 @@ class Event
 			'$show_map_label' => DI::l10n()->t('Show map'),
 			'$hide_map_label' => DI::l10n()->t('Hide map'),
 			'$map_btn_label'  => DI::l10n()->t('Show map'),
-			'$location'       => $location
+			'$location'       => self::locationToTemplateVars($item['event-location']),
 		]);
 
 		return $return;
@@ -984,7 +981,7 @@ class Event
 	 * 'coordinates' => Latitude and longitude (e.g. '48.864716,2.349014').<br>
 	 * @throws \Friendica\Network\HTTPException\InternalServerErrorException
 	 */
-	private static function locationToArray(string $s = ''): array
+	private static function locationToTemplateVars(string $s = ''): array
 	{
 		if ($s == '') {
 			return [];

src/Module/Admin/PhpInfo.php

@@ -30,6 +30,8 @@ class PhpInfo extends BaseAdmin
 	{
 		self::checkAdminAccess();
 
+		self::checkFormSecurityTokenForbiddenOnError('phpinfo', 't');
+
 		phpinfo();
 		System::exit();
 	}

src/Module/Attach.php

@@ -65,11 +65,7 @@ class Attach extends BaseModule
 		// error in Chrome for filenames with commas in them
 		header('Content-type: ' . $item['filetype']);
 		header('Content-length: ' . $item['filesize']);
-		if (isset($_GET['attachment']) && $_GET['attachment'] === '0') {
+		header('Content-disposition: attachment; filename="' . $item['filename'] . '"');
-			header('Content-disposition: filename="' . $item['filename'] . '"');
-		} else {
-			header('Content-disposition: attachment; filename="' . $item['filename'] . '"');
-		}
 
 		echo $data;
 		System::exit();

src/Module/BaseAdmin.php

@@ -104,7 +104,7 @@ abstract class BaseAdmin extends BaseModule
 				'logsview'     => ['admin/logs/view'    , DI::l10n()->t('View Logs')              , 'viewlogs'],
 			]],
 			'diagnostics' => [DI::l10n()->t('Diagnostics'), [
-				'phpinfo'      => ['admin/phpinfo'           , DI::l10n()->t('PHP Info')          , 'phpinfo'],
+				'phpinfo'      => ['admin/phpinfo?t=' . self::getFormSecurityToken('phpinfo'), DI::l10n()->t('PHP Info')                , 'phpinfo'],
 				'probe'        => ['probe'             , DI::l10n()->t('probe address')           , 'probe'],
 				'webfinger'    => ['webfinger'         , DI::l10n()->t('check webfinger')         , 'webfinger'],
 				'babel'        => ['babel'             , DI::l10n()->t('Babel')                   , 'babel'],

src/Module/Calendar/Event/API.php

@@ -142,7 +142,8 @@ class API extends BaseModule
 	{
 		$eventId = !empty($request['event_id']) ? intval($request['event_id']) : 0;
 		$uid     = (int)$this->session->getLocalUserId();
-		$cid     = !empty($request['cid']) ? intval($request['cid']) : 0;
+		// No overwriting event.cid on edit
+		$cid     = !empty($request['cid']) && !$eventId ? intval($request['cid']) : 0;
 
 		$strStartDateTime  = Strings::escapeHtml($request['start_text'] ?? '');
 		$strFinishDateTime = Strings::escapeHtml($request['finish_text'] ?? '');

src/Module/Debug/Babel.php

@@ -43,10 +43,11 @@ class Babel extends BaseModule
 		}
 
 		$results = [];
-		if (!empty($_REQUEST['text'])) {
+		if (!empty($request['text'])) {
-			switch (($_REQUEST['type'] ?? '') ?: 'bbcode') {
+			self::checkFormSecurityTokenForbiddenOnError('babel');
+			switch (($request['type'] ?? '') ?: 'bbcode') {
 				case 'bbcode':
-					$bbcode = $_REQUEST['text'];
+					$bbcode = $request['text'];
 					$results[] = [
 						'title'   => DI::l10n()->t('Source input'),
 						'content' => visible_whitespace($bbcode)
@@ -136,7 +137,7 @@ class Babel extends BaseModule
 					];
 					break;
 				case 'diaspora':
-					$diaspora = trim($_REQUEST['text']);
+					$diaspora = trim($request['text']);
 					$results[] = [
 						'title'   => DI::l10n()->t('Source input (Diaspora format)'),
 						'content' => visible_whitespace($diaspora),
@@ -144,7 +145,7 @@ class Babel extends BaseModule
 
 					$markdown = XML::unescape($diaspora);
 				case 'markdown':
-					$markdown = $markdown ?? trim($_REQUEST['text']);
+					$markdown = $markdown ?? trim($request['text']);
 
 					$results[] = [
 						'title'   => DI::l10n()->t('Source input (Markdown)'),
@@ -169,7 +170,7 @@ class Babel extends BaseModule
 					];
 					break;
 				case 'html' :
-					$html = trim($_REQUEST['text']);
+					$html = trim($request['text']);
 					$results[] = [
 						'title'   => DI::l10n()->t('Raw HTML input'),
 						'content' => visible_whitespace($html),
@@ -239,7 +240,7 @@ class Babel extends BaseModule
 					];
 					break;
 				case 'twitter':
-					$json = trim($_REQUEST['text']);
+					$json = trim($request['text']);
 
 					if (file_exists('addon/twitter/twitter.php')) {
 						require_once 'addon/twitter/twitter.php';
@@ -302,13 +303,14 @@ class Babel extends BaseModule
 		$tpl = Renderer::getMarkupTemplate('babel.tpl');
 		$o = Renderer::replaceMacros($tpl, [
 			'$title'         => DI::l10n()->t('Babel Diagnostic'),
-			'$text'          => ['text', DI::l10n()->t('Source text'), $_REQUEST['text'] ?? '', ''],
+			'$form_security_token' => self::getFormSecurityToken('babel'),
-			'$type_bbcode'   => ['type', DI::l10n()->t('BBCode'), 'bbcode', '', (($_REQUEST['type'] ?? '') ?: 'bbcode') == 'bbcode'],
+			'$text'          => ['text', DI::l10n()->t('Source text'), $request['text'] ?? '', ''],
-			'$type_diaspora' => ['type', DI::l10n()->t('Diaspora'), 'diaspora', '', (($_REQUEST['type'] ?? '') ?: 'bbcode') == 'diaspora'],
+			'$type_bbcode'   => ['type', DI::l10n()->t('BBCode'), 'bbcode', '', (($request['type'] ?? '') ?: 'bbcode') == 'bbcode'],
-			'$type_markdown' => ['type', DI::l10n()->t('Markdown'), 'markdown', '', (($_REQUEST['type'] ?? '') ?: 'bbcode') == 'markdown'],
+			'$type_diaspora' => ['type', DI::l10n()->t('Diaspora'), 'diaspora', '', (($request['type'] ?? '') ?: 'bbcode') == 'diaspora'],
-			'$type_html'     => ['type', DI::l10n()->t('HTML'), 'html', '', (($_REQUEST['type'] ?? '') ?: 'bbcode') == 'html'],
+			'$type_markdown' => ['type', DI::l10n()->t('Markdown'), 'markdown', '', (($request['type'] ?? '') ?: 'bbcode') == 'markdown'],
+			'$type_html'     => ['type', DI::l10n()->t('HTML'), 'html', '', (($request['type'] ?? '') ?: 'bbcode') == 'html'],
 			'$flag_twitter'  => file_exists('addon/twitter/twitter.php'),
-			'$type_twitter'  => ['type', DI::l10n()->t('Twitter Source / Tweet URL (requires API key)'), 'twitter', '', (($_REQUEST['type'] ?? '') ?: 'bbcode') == 'twitter'],
+			'$type_twitter'  => ['type', DI::l10n()->t('Twitter Source / Tweet URL (requires API key)'), 'twitter', '', (($request['type'] ?? '') ?: 'bbcode') == 'twitter'],
 			'$results'       => $results,
 			'$submit'        => DI::l10n()->t('Submit'),
 		]);

view/templates/babel.tpl

@@ -1,6 +1,7 @@
 <div id="babel" class="generic-page-wrapper">
 	<h2>{{$title}}</h2>
 	<form action="babel" method="post" class="panel panel-default">
+		<input type="hidden" name="form_security_token" value="{{$form_security_token}}">
 		<div class="panel-body">
 			<div class="form-group">
 				{{include file="field_textarea.tpl" field=$text}}
@@ -30,4 +31,4 @@
 		{{/foreach}}
 	</div>
 </div>
-{{/if}}
+{{/if}}

view/theme/frio/templates/event_stream_item.tpl

@@ -23,7 +23,7 @@
 						</span>
 						{{if $location.name}}
 						<span role="presentation" aria-hidden="true"> · </span>
-						<span class="event-location event-card-location">{{$location.name nofilter}}</span>
+						<span class="event-location event-card-location">{{$location.name}}</span>
 						{{/if}}
 					</div>
 					<div class="event-card-profile-name profile-entry-name">