hoist by one's own petard in German
hoist by one's own petard in German
mit den eigenen Waffen schlagen
(idiomatic) Hurt or destroyed by one's own plot or device intended for another; "blown up by one's own bomb".
wer andern eine Grube gräbt, fällt selbst hinein
(idiomatic) Hurt or destroyed by one's own plot or device intended for another; "blown up by one's own bomb".