WAF Bypass Techniques Research · Hacking Project

Research, reproduce, and document WAF evasion techniques and the concrete rule-tuning that mitigates each.

**The problem**
WAFs are frequently deployed as a compliance checkbox, but attackers bypass them with encoding tricks, HTTP parameter pollution, request smuggling, verb tampering, and payload obfuscation. Defenders who never test their WAF against evasion techniques operate with a false sense of protection. There is a shortage of structured, reproducible WAF-evasion knowledge tied to concrete mitigations.

**What you'll build**
Systematically research and catalog WAF bypass classes against multiple engines (ModSecurity/CRS, cloud WAFs) using a controlled vulnerable app, testing encoding evasions, canonicalization gaps, HTTP request smuggling, and normalization mismatches. Quantify which paranoia levels and rule tunings close each bypass, and deliver a defensive hardening guide with regression tests.

**Objective** — Research, reproduce, and document WAF evasion techniques and the concrete rule-tuning that mitigates each.

**Expected outcome** — A reproducible bypass catalog per engine, a payload/regression test suite, and a WAF-hardening guide mapping each evasion to its mitigation.

**Difficulty** — Advanced — requires deep HTTP and parser-differential knowledge plus multi-engine evasion experimentation.

**Primary category** — AppSec; Secondary = Penetration Testing, Detection Engineering, Security Research

**Security domains** — Primary = Security Research; Secondary = Red Team, AppSec, DevSecOps, Purple Team

**Technical focus** — HTTP request smuggling, parser differentials, encoding/obfuscation evasion, HTTP parameter pollution, canonicalization gaps, CRS paranoia tuning, regex evasion, verb/method tampering, regression testing

**Core technologies** — Languages: Python, JavaScript; Frameworks/Libraries: requests, custom fuzzers, OWASP CRS; Security Tools: Burp Suite, ffuf/wfuzz, sqlmap tamper scripts, ModSecurity, mitmproxy, Smuggler; Cloud/Infra: Docker, cloud WAF trials (AWS WAF/Cloudflare) for testing; AI/Data: payload mutation analytics; Databases: SQLite (catalog)

**Where it's valued** — AppSec consulting, SaaS, fintech, e-commerce, MSSPs, WAF vendors

**Careers it builds toward** — Application Security Engineer, Offensive Security Researcher, Penetration Tester, Detection Engineer, DevSecOps Engineer

**Framework alignment**
• MITRE ATT&CK: Exploit Public-Facing Application (T1190), Impair Defenses (T1562), Application Layer Protocol (T1071)
• NIST CSF 2.0: Identify (ID.RA), Protect (PR.PS), Detect (DE.CM)
• OWASP: A03 Injection, A05 Security Misconfiguration, A06 Vulnerable Components; API8 Security Misconfiguration
• CIS Controls v8: 16 Application Software Security, 13 Network Monitoring, 18 Penetration Testing