Complex sentence: Such methods are intended to capture highly sensitive information such as cryptographic keys, key-rings, passwords or unencrypted plaintext, typically without the victim (s) realising this has occurred.
Split into simpler sentences: Such methods are intended to capture highly sensitive information e.g. cryptographic keys, key-rings, passwords or unencrypted plaintext. Typically, the capture takes place without the victim (s) realising it has occurred.