The Rocket.Chat desktop application 2.17.11 opens external links without user interaction.

Rocket.Chat through 3.4.2 allows XSS where an attacker can send a specially crafted message to a channel or in a direct message to the client which results in remote code execution on the client side.

Rocket.Chat before 2.1.0 allows XSS via a URL on a ![title] line.

A reflected XSS issue was discovered in the registration form in Rocket.Chat before 0.66. When one creates an account, the next step will ask for a username. This field will not save HTML control characters but an error will be displayed that shows the attempted username unescaped via packages/rocketchat-ui-login/client/username/username.js in packages/rocketchat-ui-login/client/username/username.html.

An XSS issue was discovered in packages/rocketchat-mentions/Mentions.js in Rocket.Chat before 0.65. The real name of a username is displayed unescaped when the user is mentioned (using the @ symbol) in a channel or private chat. Consequently, it is possible to exfiltrate the secret token of every user and also admins in the channel.

Rocket.Chat Server version 0.59 and prior is vulnerable to a NoSQL injection leading to administrator account takeover

A Server-Side Request Forgery (SSRF) affects Rocket.Chat's Twilio webhook endpoint before version 6.10.1.