analyzing-malicious-url-with-urlscan
URLScan.io is a free service for scanning and analyzing suspicious URLs. It captures screenshots, DOM content, HTTP transactions, JavaScript behavior, and network connections of web pages in an isolat
By mukul975 · 414 installs
npx skills add mukul975/anthropic-cybersecurity-skills --skill analyzing-malicious-url-with-urlscan
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Analyzing Malicious URL with URLScan
Overview
URLScan.io is a free service for scanning and analyzing suspicious URLs. It captures screenshots, DOM content, HTTP transactions, JavaScript behavior, and network connections of web pages in an isolated environment. This skill covers using URLScan's web interface and API to investigate phishing URLs, credential harvesting pages, and malicious redirects without exposing the analyst's system to risk.
When to Use
When investigating security incidents that require analyzing malicious url with urlscan
When building detection rules or threat hunting queries for this domain
When SOC analysts need structured procedures for this analysis type
When validating security monitoring coverage for related attack techniques
Prerequisites
URLScan.io account (free tier available, API key for automation)
Python 3.8+ with requests library
Understanding of HTTP protocols and web technologies
Familiarity with phishing URL patterns
Key Concepts
URLScan Capabilities
1. Safe browsing : Renders URLs in isolated Chromium instance
2. Screenshot capture : Visual snapshot of the rendered page
3. DOM analysis : Full HTML content after JavaScript execution
4. Network log : All HTTP requests made by the page (HAR format)
5. Certificate analysis : SSL/TLS certificate details
6. Technology detection : Identifies web frameworks and libraries
7. IP/ASN mapping : Infrastructure intelligence
8. Verdict : Community and automated classification
Phishing URL Red Flags
Newly registered domains (< 30 days)
Free hosting services (Wix, GitHub Pages, Firebase)
URL shorteners hiding final destination
Excessive subdomain depth (login.microsoft.com.evil.com)
Brand name in subdomain or path, not domain
Non standard ports
Data URIs or base64 encoded content
JavaScript heavy pages with minimal HTML
Workflow
Step 1: Submit URL to URLScan
Step 2: Analyze Results
Review screenshot for brand impersonation
Check redirects and final destination URL
Examine DOM for credential input forms
Review network requests for data exfiltration endpoints
Check SSL certificate validity and issuer
Step 3: Extract IOCs
Domains and IPs contacted
URLs in redirect chain
SHA 256 hashes of page resources
JavaScript file hashes
Step 4: Cross Reference with Threat Intelligence
Use the scripts/process.py to automate URL scanning, extract IOCs, and cross reference with VirusTotal, PhishTank, and Google Safe Browsing.
Tools & Resources
URLScan.io : https://urlscan.io/
URLScan API : https://urlscan.io/docs/api/
VirusTotal URL Scanner : https://www.virustotal.com/
PhishTank : https://phishtank.org/
Google Safe Browsing : https://transparencyreport.google.com/safe browsing/search
Any.Run : https://any.run/ (interactive sandbox)
Hybrid Analysis : https://www.hybrid analysis.com/
Validation
Successfully scan a suspicious URL via API
Extract screenshot and identify brand impersonation
Document complete redirect chain
Generate IOC list from scan results
Cross reference findings with at least 2 threat intelligence sources