This tweet gives a general guideline for bypassing a Web Application Firewall (WAF). It suggests that to bypass a WAF, the first step is to understand how the payload you plan to use is reflected in the Document Object Model (DOM) of the web page. Once you understand how your payload appears in the HTML, you can craft it in a way that avoids detection by the WAF. This approach is universal and applies to many types of vulnerabilities such as Cross-Site Scripting (XSS), SQL Injection (SQLi), or Remote Code Execution (RCE). The tweet emphasizes an important method in WAF bypass: analyzing the output of the payload in the application's DOM to find a working bypass strategy. Such a method helps to evade filters by adjusting payload encoding or structure so that the malicious part is not detected by the WAF but still executes as intended in the browser or backend.
For more details, check out the original tweet here: https://twitter.com/suslu7616/status/1999059074063962462