websocket-test

Tests WebSocket endpoints for authentication bypass, CSWSH, IDOR, injection, and replay vulnerabilities.

2|1|Updated Aug 28, 2026
One-click install
npx skills add https://github.com/lycheer1126/xs-bigdan --skill websocket-test-lycheer1126
Or copy as Structured Prompt for Agent
Please help me install this Agent Skill.
Skill: websocket-test
Source: https://github.com/lycheer1126/xs-bigdan/tree/main/knowledge/skills/websocket_test
Command: npx skills add https://github.com/lycheer1126/xs-bigdan --skill websocket-test-lycheer1126

SYSTEM DOCUMENTATION & REQUIREMENTS

💡 This Skill requires websockets.

What problem does it solve? WebSocket connections often skip the security scrutiny applied to HTTP APIs, leaving real-time channels exposed to authentication bypass, cross-site hijacking, and unauthorized message subscriptions. This Skill provides a systematic methodology for locating and testing WebSocket endpoints during authorized security assessments. ## Core Features & Use Cases - Endpoint Discovery: Locates WebSocket endpoints by searching JavaScript for new WebSocket(, ws://, wss://, Socket.IO, and STOMP patterns. - Authentication & Authorization Testing: Covers post-handshake token switching, unauthenticated connections, and IDOR via tampered channel/room/user IDs. - Attack Coverage: Includes CSWSH origin validation checks, message injection (XSS/SQLi/command), replay attacks, and connection exhaustion DoS verification. - Use Case: During an authorized pentest of a chat application, grep the site's JS for wss:// endpoints, then use the provided Python scripts to verify whether modifying a roomId in a subscribe message leaks another user's private messages. ## Quick Start Ask the agent to run the WebSocket security test against the authorized target, starting by extracting all ws:// and wss:// endpoints from the downloaded JavaScript files.

Frequently Asked Questions about websocket-test

High-intent search queries and answers about installing and using this skill.

FAQPage Schema
How do I find WebSocket endpoints in a web application?

Search the application's JavaScript files for patterns like new WebSocket(, ws://, wss://, io(, socket.emit, and Stomp.client. Socket.IO endpoints commonly appear at /socket.io/?EIO=4&transport=websocket and can be probed with curl.

How to test WebSocket authentication bypass?

Establish a connection with a valid token, then send a message containing a different user's token or userId. If the server processes subsequent messages under the new identity without re-verification, the endpoint is vulnerable to post-handshake authentication bypass.

What is Cross-Site WebSocket Hijacking and how do I detect it?

CSWSH occurs when a WebSocket server accepts upgrade requests from any Origin, letting an attacker's page open an authenticated connection using the victim's cookies. Detect it by sending an upgrade request with a foreign Origin header and checking for a 101 Switching Protocols response.

Can WebSocket messages be replayed to repeat transactions?

Yes, if the server lacks replay protection. Capture messages with Burp or a proxy, then resend actions like order creation multiple times; if the server accepts duplicates, the endpoint is vulnerable to replay attacks.

What are the limits of WebSocket IDOR testing?

Testing should only use your own test accounts and modify channel, room, or conversation IDs to check for cross-user message access. Proof of unauthorized subscription should be limited to a small number of messages, never bulk interception of other users' traffic.