Injured or harmed by one's own action or plan intended to harm someone else.

आत्मघात का शिकार हो जाना

English Usage: He plotted against his colleague, but ended up being hoist by his own petard.

Hindi Usage: उसने अपने सहयोगी के खिलाफ साजिश रची, लेकिन खुद ही आत्मघात का शिकार हो गया।