Pieck is a stealth virus, so changes made to MBR and EXE files are not visible as long as the virus is resident.
Pieck activates on third of March, every year. At this date, it decrypt and display this message:
Podaj haslo ?
Which means "Password?". The correct password is 'PIECK'. If an incorrect answer is given, the virus displays 'Blad!' (which means 'Bad!') and makes the machine unbootable. Correct password is greeted with a new message:
Pozdrowienia dla wynchowankow Pieck'a.
('Greetings to "wychowankow" Pieck').
Pieck was known to be in the wild in Eastern Europe in 1995 and in Germany in early 1996.
Variant:Pieck.4444 (Kaczor)
If the word "kaczor" is typed on the keyboard of an infected machine, the virus disinfects the MBR and displays this text:
Zrobione.
If the word "test" is written, the virus displays these texts:
Wersja
Kodowanie
Licznik HD
Otherwise this variant is similar to Pieck.2016 but activates by shaking the screen rapidly causing serious screen flicker on every 3rd of March. It also has some problems infecting files on 3.5" floppies.
Pieck.4444 is known to be in the wild internationally.