Avoid accepting a rogue key. Use a communication channel other than email to verify the fingerprint of your correspondent’s key.
Ḍmen iman-ik ur tqebbleḍ ara tisura ur nettusireg ara. Seqdec abadu-nniḍen n teywalt ɣef yimayl i usenqed n udsil umḍin n tsarut n unermis-ik.