From 101d18ce97d9854774bc2fb00f5e9f2082ce0c1f Mon Sep 17 00:00:00 2001 From: Sergey Biryukov Date: Thu, 12 Dec 2019 18:43:19 +0000 Subject: [PATCH] Update `wp_kses_bad_protocol()` to recognize `:` on uri attributes, MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit `wp_kses_bad_protocol()` makes sure to validate that uri attributes don’t contain invalid/or not allowed protocols. While this works fine in most cases, there’s a risk that by using the colon html5 named entity, one is able to bypass this function. Brings r46895 to the 4.3 branch. Props: xknown, nickdaugherty, peterwilsoncc. Built from https://develop.svn.wordpress.org/branches/4.3@46911 git-svn-id: http://core.svn.wordpress.org/branches/4.3@46711 1a063a9b-81f0-0310-95a4-ce76da25c4cd --- wp-includes/kses.php | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/wp-includes/kses.php b/wp-includes/kses.php index 798804654e..093ae56d8f 100644 --- a/wp-includes/kses.php +++ b/wp-includes/kses.php @@ -1393,7 +1393,7 @@ function wp_kses_html_error($string) { */ function wp_kses_bad_protocol_once($string, $allowed_protocols, $count = 1 ) { $string = preg_replace( '/(�*58(?![;0-9])|�*3a(?![;a-f0-9]))/i', '$1;', $string ); - $string2 = preg_split( '/:|�*58;|�*3a;/i', $string, 2 ); + $string2 = preg_split( '/:|�*58;|�*3a;|:/i', $string, 2 ); if ( isset($string2[1]) && ! preg_match('%/\?%', $string2[0]) ) { $string = trim( $string2[1] ); $protocol = wp_kses_bad_protocol_once2( $string2[0], $allowed_protocols );