This tweet describes a WAF bypass technique specifically targeting XSS (Cross-Site Scripting) vulnerabilities. The payload used is an image tag with the OnMouseover event triggering a JavaScript print function: <img src=a OnMouseover=`${print()}`>. The tweet suggests encoding this payload in HTML and URL formats to bypass filters and WAF protections. This bypass method exploits the way some WAFs and input validation filters handle encoded payloads, allowing an attacker to execute scripts via mouseover events despite protections. The tweet is relevant for bug bounty hunters and security researchers focusing on bypassing WAFs and filters for XSS attacks. The exact WAF vendor is not mentioned, indicating the method might be general or tested against multiple WAFs.
For more insights, check out the original tweet here: https://twitter.com/ariverapoblet/status/1938588204807999792. And don’t forget to follow @ariverapoblet for more exciting updates in the world of cybersecurity.