This tweet highlights an important point about web application firewalls (WAFs) and security in general. It says that even when a WAF is in place and parameterized queries are used to prevent SQL Injection, attackers can still bypass these protections. The reason is that instead of trying to exploit syntax-based vulnerabilities, attackers can look for logic flaws in the application. Logic flaws are weaknesses in the way an application is designed or how it processes data. They do not rely on common injection techniques or malformed input but rather on making the application behave in unintended ways. This bypass approach is significant because WAFs and parameterized queries typically focus on blocking malicious syntax or injections, not on understanding the application's logic. Therefore, it is crucial for developers and security teams to also consider logic flaw vulnerabilities during design, testing, and code review phases to complement WAF protections and other syntax-based defenses. Simply put, security cannot rely solely on technology like WAFs and parameterized queries; it also requires thorough understanding and testing of the application's intended behavior to catch logic errors that attackers might exploit.
For more insights, check out the original tweet here: https://twitter.com/yemenisme/status/2034394140687962353