Changeset 41448

Timestamp:

09/19/2017 01:41:52 PM (7 years ago)

Author:

aaroncampbell

Message:

oEmbed: Add extra hardening around allowed HTML for improved sandboxing.

File:

• trunk/src/wp-includes/embed.php (modified) (2 diffs)

trunk/src/wp-includes/embed.php

@@ -754 +754 @@
     $html = $content[1] . $content[2];
 
+    preg_match( '/ src=([\'"])(.*?)\1/', $html, $results );
+
+    if ( ! empty( $results ) ) {
+        $secret = wp_generate_password( 10, false );
+
+        $url = esc_url( "{$results[2]}#?secret=$secret" );
+        $q = $results[1];
+
+        $html = str_replace( $results[0], ' src=' . $q . $url . $q . ' data-secret=' . $q . $secret . $q, $html );
+        $html = str_replace( '<blockquote', "<blockquote data-secret=\"$secret\"", $html );
+    }
+
+    $allowed_html['blockquote']['data-secret'] = true;
+    $allowed_html['iframe']['data-secret'] = true;
+
+    $html = wp_kses( $html, $allowed_html );
+
     if ( ! empty( $content[1] ) ) {
         // We have a blockquote to fall back on. Hide the iframe by default.
@@ -760 +777 @@
     }
 
-    $html = str_replace( '<iframe', '<iframe class="wp-embedded-content" sandbox="allow-scripts" security="restricted"', $html );
-
-    preg_match( '/ src=[\'"]([^\'"]*)[\'"]/', $html, $results );
-
-    if ( ! empty( $results ) ) {
-        $secret = wp_generate_password( 10, false );
-
-        $url = esc_url( "{$results[1]}#?secret=$secret" );
-
-        $html = str_replace( $results[0], " src=\"$url\" data-secret=\"$secret\"", $html );
-        $html = str_replace( '<blockquote', "<blockquote data-secret=\"$secret\"", $html );
-    }
+    $html = str_ireplace( '<iframe', '<iframe class="wp-embedded-content" sandbox="allow-scripts" security="restricted"', $html );
 
     return $html;