From Longman Dictionary of Contemporary Englishfall/get into the wrong handsfall/get into the wrong handsif something secret or dangerous falls into the wrong hands, it is discovered by someone who may use it to harm people → wrong
Examples from the Corpus
fall/get into the wrong hands• A crossed cheque therefore gives some protection against fraud if it falls into the wrong hands.• And images of Kurds on tape could fall into the wrong hands.• But some gun dealers have stopped selling replicas, because they're worried about them falling into the wrong hands.• I will never allow Kirsty to fall into the wrong hands.• Pentagon officials say they have already had some success reducing the risk that nuclear materials will fall into the wrong hands.• Voice over Mr Foulkes is seeking Government safeguards to prevent Rayo from falling into the wrong hands.• Cards falling into the wrong hands cost the industry three hundred pounds every minute. 