Refers to dubious or unverified information, often with a sensational or mysterious tone. The 怪 (kai) element suggests something strange or suspicious.
Dubious rumors are spreading online.
He always talks about nothing but gossip.
Compound of 怪 (kai, 'suspicious, strange') and 情報 (jōhō, 'information'). The exact origin is uncertain, but it likely emerged in modern Japanese to describe dubious or sensational reports.