In the postal service of the Belarusian portal TUT.by there is no check for authorization of the user when marking letters as spam. As a result, an attacker can attack any user by sending all his emails from the INBOX folder to the Trash folder. If you type in the browser just such a link mail.tut.by/cgi-bin/go.cgi?address=X&folder=INBOX&server=mail.tut.by&messages=Ymail.tut.by/cgi-bin/go.cgi?address=X&folder=INBOX&server=mail.tut.by&messages=Y , where X is the username and Y is the letter number, the corresponding letter will be moved to the trash.
The value of Y can be equal to a specific letter number or to several, separated by commas.