Lab: Manipulating the Web Socket handshake to exploit vulnerabilities
Summary: PortSwigger's lab presents an online shop whose live chat runs over WebSockets and whose XSS filter is described as aggressive but flawed. The exercise is to edit and resend a WebSocket message carrying a basic XSS payload, add a header to the handshake request to spoof an IP address, and send an obfuscated payload that triggers an alert() in the support agent's browser.
Key Takeaway: The target here is the support agent's browser, so a filter that looks aggressive on the surface still let an obfuscated payload through once the handshake was manipulated to spoof an IP address.
Read the original at PortSwigger Research ↗
- Topics
- Vulnerabilities & Patching
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