What type of application flaw did Steve discover when he was able to insert a malicious query into a webpage?

When Steve was able to insert a malicious query into a webpage, he encountered a flaw known as improper input handling. This type of vulnerability occurs when an application does not correctly validate, sanitize, or restrict the user inputs that it receives. As a result, attackers can manipulate queries or commands that the application processes, leading to malicious activities such as SQL injection.

Improper input handling is critical because it can open the door to various attack vectors that can compromise data integrity, privacy, and even the security of the entire application. For example, in the case of SQL injection, an attacker may exploit the flaw to execute arbitrary SQL queries against the database, potentially extracting sensitive data or modifying the underlying data structures.

This concept emphasizes the importance of proper validation measures and input sanitization techniques in the development of web applications to mitigate the risks associated with untrusted inputs. Hence, recognizing improper input handling as the type of flaw is crucial for improving application security and protecting against exploitation.