The tweet mentions using printf to bypass a WAF and receiving ANSI back in the terminal. This technique can be used for various types of vulnerabilities. It implies that the WAF was unable to block the printf payload, allowing it to pass through. The use of ANSI in the terminal suggests potential evasion strategies through formatting. These techniques are persistent and difficult to eliminate, indicating a loophole in the WAF detection. Further analysis and testing are recommended to understand the full implications of this bypass technique.
Original tweet: https://twitter.com/evrnyalcin/status/1865095809580060679