Is it Whatsapp or a Samsung privacy breach?

[AC Question]

Whats app or samsung privacy breach

I have no knowledge of Whats app on a PC, I have a mobile with whats app and a stranger receives my photos on her PC - not on her mobile, she has a samsung and i have an apple, I have zero idea where to start and I am certain this is a privacy breach. I have a microsoft account I never use, and icloud account, how private photos are received by a stranger is beyond me. I have totally stumped on where to start