To prevent this, you should concatenate user input directly into SQL strings. Instead:
The attacker sees this error in the HTTP response. Because the error contains the 1 (the result of the subquery), the attacker knows the injection worked. : To prevent this, you should concatenate user input
The initial '{KEYWORD}' AND ... attempts to break out of a single-quoted string literal within a vulnerable SQL query. : To prevent this
When Oracle tries to parse the resulting string (e.g., <:qbqvq1qqbqq> ), it realizes it is not a valid XML format. It then returns an error message like: LPX-00110: XML parsing failed... at '<:qbqvq1qqbqq>' . To prevent this, you should concatenate user input