> For the complete documentation index, see [llms.txt](https://hacking-notes.jord4n.pro/llms.txt). Markdown versions of documentation pages are available by appending `.md` to page URLs; this page is available as [Markdown](https://hacking-notes.jord4n.pro/web/authentication.md). # Authentication Authentication bypass, user enumeration, password reset flaws, 2FA bypass, brute force, session cookies, and account takeover. Authentication notes for PortSwigger Web Security Academy labs, focused on practical testing steps, Burp Suite validation, payload behavior, and exploitation workflow. ## Testing Workflow 1. Identify the vulnerable feature and the relevant request, parameter, header, cookie, or browser-side sink. 2. Reproduce the behavior in Burp Suite with a minimal payload before escalating the attack. 3. Validate impact with a clear proof of concept, such as account access, data disclosure, code execution, SSRF, or state change. 4. Keep payloads, URLs, tokens, and lab credentials unchanged while documenting the exploitation path. ## Labs


2FA Bypass via Brute Force
Broken 2FA Logic
Broken Brute-Force Protection with IP-Based Blocking
Broken Brute-Force Protection with Multiple Credentials per Request
Brute Forcing a Persistent Session Cookie
Flawed Logic in Password Reset
Offline Password Cracking
Password Brute Force via Password Change Functionality
Password Reset Poisoning via Middleware
Simple 2FA Bypass
Username Enumeration via Account Lockout
Username Enumeration via Different Responses
Username Enumeration via Response Timing
Username Enumeration via Subtly Different Responses

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