Fix handling of base64-encoded attachments with extra spaces (#1490111)

CHANGELOG

@@ -57,6 +57,7 @@ CHANGELOG Roundcube Webmail
 - Fix font style display issue in HTML messages with styled <span> elements (#1490101)
 - Fix download of attachments that are part of TNEF message (#1490091)
 - Fix handling of uuencoded messages if messages_cache is enabled (#1490108)
+- Fix handling of base64-encoded attachments with extra spaces (#1490111)
 
 RELEASE 1.0.3
 -------------

program/lib/Roundcube/rcube_imap_generic.php

@@ -2675,7 +2675,7 @@ class rcube_imap_generic
 
                     // BASE64
                     if ($mode == 1) {
-                        $line = rtrim($line, "\t\r\n\0\x0B");
+                        $line = preg_replace('|[^a-zA-Z0-9+=/]|', '', $line);
                         // create chunks with proper length for base64 decoding
                         $line = $prev.$line;
                         $length = strlen($line);