Vaultpress security alert

After installing the latest version I received this security aler from vault press
DES.php
/wp-content/plugins/wp-mail-smtp/vendor/phpseclib/phpseclib/phpseclib/Crypt
Generic.Hidden.Code.2
This file contains suspicious hidden code, and should be checked for recent changes, or malicious code. Often hackers try to hide their hack attempts by obfuscating their attack code, to make it harder to detect. VaultPress has detected a string of suspicious characters in this file. Please check your backup history for recent changes to this file, or contact a Safekeeper if you are unsure.
Repair Threat
Ignore Threat
1 File Affected
Code identified Showing pre-processed file

        $block = ($shuffleip[ $r        & 0xFF] & "\x80\x80\x80\x80\x80\x80\x80\x80") |
700
                 ($shuffleip[($r >>  8) & 0xFF] & "\x40\x40\x40\x40\x40\x40\x40\x40") |
701
                 ($shuffleip[($r >> 16) & 0xFF] & "\x20\x20\x20\x20\x20\x20\x20\x20") |
…
739
        return ($shuffleinvip[($r >> 24) & 0xFF] & "\x80\x80\x80\x80\x80\x80\x80\x80") |
740
               ($shuffleinvip[($l >> 24) & 0xFF] & "\x40\x40\x40\x40\x40\x40\x40\x40") |
741
               ($shuffleinvip[($r >> 16) & 0xFF] & "\x20\x20\x20\x20\x20\x20\x20\x20") |
…
1220
            $key = ($this->shuffle[$pc1map[ $r        & 0xFF]] & "\x80\x80\x80\x80\x80\x80\x80\x00") |
1221
                   ($this->shuffle[$pc1map[($r >>  8) & 0xFF]] & "\x40\x40\x40\x40\x40\x40\x40\x00") |
1222
                   ($this->shuffle[$pc1map[($r >> 16) & 0xFF]] & "\x20\x20\x20\x20\x20\x20\x20\x00") |
…
1374
                        ($shuffleip[ $r        & 0xFF] & "\x80\x80\x80\x80\x80\x80\x80\x80") |
1375
                        ($shuffleip[($r >>  8) & 0xFF] & "\x40\x40\x40\x40\x40\x40\x40\x40") |
1376
                        ($shuffleip[($r >> 16) & 0xFF] & "\x20\x20\x20\x20\x20\x20\x20\x20") |
…
1417
                    ($shuffleinvip[($l >> 24) & 0xFF] & "\x80\x80\x80\x80\x80\x80\x80\x80") |
1418
                    ($shuffleinvip[($r >> 24) & 0xFF] & "\x40\x40\x40\x40\x40\x40\x40\x40") |
1419
                    ($shuffleinvip[($l >> 16) & 0xFF] & "\x20\x20\x20\x20\x20\x20\x20\x20") |
Showing pre-processed file