Update wp_kses_bad_protocol() to recognize : on uri attributes,

`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 4.4 branch.

Props: xknown, nickdaugherty, peterwilsoncc.
Built from https://develop.svn.wordpress.org/branches/4.4@46912


git-svn-id: http://core.svn.wordpress.org/branches/4.4@46712 1a063a9b-81f0-0310-95a4-ce76da25c4cd
This commit is contained in:
Sergey Biryukov 2019-12-12 18:44:21 +00:00
parent 25a94707d9
commit 23ac697ad8

View File

@ -1396,7 +1396,7 @@ function wp_kses_html_error($string) {
*/
function wp_kses_bad_protocol_once($string, $allowed_protocols, $count = 1 ) {
$string = preg_replace( '/(&#0*58(?![;0-9])|&#x0*3a(?![;a-f0-9]))/i', '$1;', $string );
$string2 = preg_split( '/:|&#0*58;|&#x0*3a;/i', $string, 2 );
$string2 = preg_split( '/:|&#0*58;|&#x0*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 );