XSStrike

What is XSStrike?

XSStrike is a Python-based Cross-Site Scripting (XSS) detection and exploitation framework. Unlike basic scanners that blindly inject static payloads, XSStrike analyzes the server's response to understand how the input is being reflected and generates context-aware payloads accordingly. It includes a built-in fuzzer, DOM-based XSS crawler, WAF detection, and an intelligent payload generator — making it one of the most capable open-source XSS testing tools available for authorized web application penetration testing.

Installation

# Update packages
sudo apt update

# Install via apt (Kali)
sudo apt install xsstrike -y

# OR clone from GitHub (recommended — always latest)
git clone https://github.com/s0md3v/XSStrike.git
cd XSStrike
pip3 install -r requirements.txt

# Run directly
python3 xsstrike.py --help

Basic Usage

XSStrike requires a target URL with at least one parameter to test. The -u flag specifies the target. Parameters in the URL are automatically detected and fuzzed.

# Scan a single URL parameter for XSS
python3 xsstrike.py -u "http://target.com/search?q=test"

# Test a URL and crawl the site for more injection points
python3 xsstrike.py -u "http://target.com" --crawl

# Test a POST request parameter
python3 xsstrike.py -u "http://target.com/login" --data "username=test&password=test"

# Blind XSS testing (payload fires out-of-band)
python3 xsstrike.py -u "http://target.com/search?q=test" --blind

# Fuzzing mode — try a large payload set
python3 xsstrike.py -u "http://target.com/search?q=test" --fuzzer

# DOM-based XSS crawl (JavaScript sink analysis)
python3 xsstrike.py -u "http://target.com" --dom

WAF Detection & Bypass

XSStrike automatically fingerprints Web Application Firewalls and adjusts its payloads to attempt bypass. Use these flags to fine-tune behavior against hardened targets.

# Check if a WAF is present before attacking
python3 xsstrike.py -u "http://target.com/search?q=test" --skip-dom

# Encode payloads to bypass input filters
python3 xsstrike.py -u "http://target.com/search?q=test" --encode

# Skip DOM crawling for faster WAF-aware scans
python3 xsstrike.py -u "http://target.com/search?q=test" --skip

# Add a custom header (e.g. bypass IP-based restrictions)
python3 xsstrike.py -u "http://target.com/search?q=test" --headers "X-Forwarded-For: 127.0.0.1"

# Add authentication cookies for testing logged-in areas
python3 xsstrike.py -u "http://target.com/profile?id=1" --cookies "session=abc123; auth=xyz"

Crawling & Multi-Parameter Testing

# Crawl entire site and test all discovered parameters
python3 xsstrike.py -u "http://target.com" --crawl -l 3
# -l: crawl depth level (default 2)

# Test all parameters in a URL at once
python3 xsstrike.py -u "http://target.com/page?id=1&name=test&search=hello"

# Log all discovered XSS vulnerabilities to a file
python3 xsstrike.py -u "http://target.com" --crawl --log-file results.txt

# Set a request timeout (seconds)
python3 xsstrike.py -u "http://target.com/search?q=test" --timeout 10

# Add a delay between requests (avoid rate limiting)
python3 xsstrike.py -u "http://target.com/search?q=test" --delay 2

Common Flags

• -u — Target URL with injectable parameter
• --data — POST body data string
• --crawl — Spider the site and test all found parameters
• --dom — Perform DOM-based XSS analysis only
• --blind — Test for blind/out-of-band XSS
• --fuzzer — Run the built-in fuzzer against the target
• --encode — Encode payloads (helps bypass basic WAFs)
• --skip — Skip DOM crawling (faster)
• --skip-dom — Skip DOM analysis entirely
• --headers — Add custom HTTP headers
• --cookies — Supply session cookies for authenticated testing
• --proxy — Route traffic through a proxy (e.g. Burp Suite)
• --delay — Delay in seconds between each request
• --timeout — HTTP request timeout in seconds
• --log-file — Save output to a log file
• -l — Crawl depth level

Using with Burp Suite

Route XSStrike traffic through Burp Suite's proxy to inspect and modify requests in real time — especially useful for testing complex authenticated sessions.

# Point XSStrike at Burp's default proxy listener
python3 xsstrike.py -u "http://target.com/search?q=test" --proxy "http://127.0.0.1:8080"

Common Use Cases

• Detecting reflected XSS in search fields, URL parameters, and form inputs
• Finding stored XSS injection points in comment fields and user profiles
• DOM-based XSS analysis in JavaScript-heavy single-page applications
• WAF bypass payload generation during authorized red team assessments
• Bug bounty hunting on web application targets that accept XSS reports
• CTF web challenges involving XSS filters and sandboxed execution contexts

Further Reading

XSStrike works best alongside Burp Suite for manual verification and dalfox as an alternative XSS scanner. For understanding XSS deeply, study the OWASP XSS Prevention Cheat Sheet and practice on deliberately vulnerable apps like DVWA, bWAPP, or the XSS labs on hackzia.site and TryHackMe. Always verify findings manually before reporting — automated scanners can produce false positives.