This tweet discusses a Web Application Firewall (WAF) bypass technique using junk data. This trick has been known for 13 years and is a universal method that can affect many types of vulnerabilities such as XSS, SQLi, and RCE. The technique involves injecting irrelevant or junk data into the request to confuse or bypass the WAF's filtering mechanisms. Because WAFs inspect traffic to block malicious payloads, adding junk data can disrupt their pattern matching or signature detection, allowing the attacker to bypass protections. The exact vendor of the WAF targeted is not mentioned, indicating this method may work against multiple vendors. Overall, this is an old yet still relevant bypass trick for evading WAFs by leveraging junk data to evade detection.
For more insights, check out the original tweet here: https://twitter.com/h4x0r_dz/status/1945886110682325143