HOIST WITH (OR BY) ONE'S OWN PETARD
Meaning of HOIST WITH (OR BY) ONE'S OWN PETARD in English
hoist with ( or by) one's own petard
having one's schemes against others backfiring on one.
→ petard
Concise Oxford English vocab.
Сжатый оксфордский словарь английского языка.
2004