Ticket #10498: 10498.diff

wp-includes/class-simplepie.php

@@ -9432 +9432 @@
                         return SimplePie_Misc::windows_1252_to_utf8($data);
                 }
                 // This is second, as behaviour of this varies only with PHP version (the middle part of this expression checks the encoding is supported).
-                elseif (function_exists('mb_convert_encoding') && @mb_convert_encoding("\x80", 'UTF-16BE', $input) !== "\x00\x80" && ($return = @mb_convert_encoding($data, $output, $input)))
+                elseif (function_exists('mb_convert_encoding') && @mb_convert_encoding("\x80", 'UTF-16BE', $input) !== "\x00\x80" && in_array( $input, mb_list_encodings() ) && ($return = @mb_convert_encoding($data, $output, $input)))
                 {
                         return $return;
                 }