A cross-site scripting vulnerability exists in Rocket.chat <v5 due to style injection in the complete chat window, an adversary is able to …

A cross-site scripting vulnerability exists in Rocket.chat <v5 due to style injection in the complete chat window, an adversary is able to manipulate not only the style of it, but will also be able to block functionality as well as hijacking the content of targeted users. Hence the payloads are stored in messages, it is a persistent attack vector, which will trigger as soon as the message gets viewed.