In the Certified Ethical Hacker (CEH) curriculum, Web Application Hacking using AI means applying artificial intelligence and machine learning to speed up and strengthen each phase of assessing web applications for security weaknesses. Ethical hackers use AI to automate repetitive tasks, uncover hidden vulnerabilities, and simulate how modern adversaries operate. During footprinting and reconnaissance, AI-powered tools can crawl websites, analyze JavaScript files, identify technology stacks, discover hidden endpoints, and map APIs much faster than manual methods. Large language models (LLMs) such as ChatGPT can generate commands for tools like Nmap, Gobuster, WhatWeb, or Nikto and help interpret their output. In vulnerability discovery, machine learning models improve fuzzing by generating intelligent, context-aware payloads instead of random inputs. AI can craft and mutate payloads for SQL injection, cross-site scripting (XSS), command injection, server-side request forgery (SSRF), and XML external entity (XXE) attacks. It can also adapt these payloads to evade web application firewalls (WAFs) and input filters. Burp Suite extensions with AI features, ShellGPT, and AI-assisted scanners help prioritize findings and reduce false positives. AI also supports source code review by detecting insecure coding patterns, hardcoded credentials, and logic flaws. For authentication testing, AI can analyze password patterns, generate targeted wordlists, and help solve or bypass CAPTCHAs. Testers must also evaluate AI-integrated applications themselves for threats such as prompt injection, insecure output handling, training data poisoning, and sensitive data leakage, as described in the OWASP Top 10 for LLM Applications. For exploitation and reporting, AI can write proof-of-concept scripts, explain exploit chains, and produce clear remediation recommendations. On the defensive side, organizations use AI for anomaly detection, behavioral analysis, and adaptive WAF rules that respond to emerging attack patterns. CEH stresses that these techniques may only be used with proper written authorization, within a defined scope, and in line with legal and ethical guidelines. The same AI capabilities that help ethical hackers also empower malicious attackers, so responsible use and strong defensive controls are essential.