diff -r 34716fd837a4 -r be944660c56a wp/wp-includes/SimplePie/Misc.php
--- a/wp/wp-includes/SimplePie/Misc.php	Tue Dec 15 15:52:01 2020 +0100
+++ b/wp/wp-includes/SimplePie/Misc.php	Wed Sep 21 18:19:35 2022 +0200
@@ -364,11 +364,12 @@
 		}
 
 		// Check that the encoding is supported
-		if (@mb_convert_encoding("\x80", 'UTF-16BE', $input) === "\x00\x80")
+		if (!in_array($input, mb_list_encodings()))
 		{
 			return false;
 		}
-		if (!in_array($input, mb_list_encodings()))
+
+		if (@mb_convert_encoding("\x80", 'UTF-16BE', $input) === "\x00\x80")
 		{
 			return false;
 		}