This post discusses a WAF bypass technique using full-width Unicode symbols. It targets vulnerabilities like Cross-Site Scripting (XSS) and Carriage Return Line Feed (CRLF) injection. The method involves replacing certain ASCII characters in the payload with their full-width Unicode equivalents, which can confuse WAFs (Web Application Firewalls) and allow the malicious payloads to pass through unchecked. This technique is useful against many WAF vendors since it's a universal approach leveraging character encoding differences rather than specific vendor weaknesses. Security researchers and penetration testers should be aware of this trick to understand how attackers might evade detection and how to improve their defensive rules.
For more insights, check out the original tweet here: https://twitter.com/XssPayloads/status/1934808315306942502