Probably has not a lot to do with your choice of bitcoin/bitcoin cash wallet... and a lot to do with keyloggers/malware etc... 
Whatever the cause, it is a good example of why people suggest moving BTC off of any private keys BEFORE attempting to claim the BCH or other fork coins from them... exposing your private key to an online environment puts coins at risk.
Whatever the cause, it is a good example of why people suggest moving BTC off of any private keys BEFORE attempting to claim the BCH or other fork coins from them... exposing your private key to an online environment puts coins at risk.