Web Socket URL poisoning (DOM-based)
Summary: PortSwigger describes DOM-based WebSocket URL poisoning, where a client-side script reads controllable data such as the URL and uses it as the target of a WebSocket connection. An attacker can construct a URL that, when visited by another user, makes that user's browser open a WebSocket connection to a server the attacker controls.
Bottom line: If the application sends sensitive data from the browser to the WebSocket server, the attacker can capture it, and if the application processes data read back from that server, the attacker can subvert its logic or deliver further client-side attacks against the user.
Read the original at PortSwigger Research ↗
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