This is most likely a blind SQL injection, testing whether you're vulnerable to SQL Injection by checking whether your server takes the specified time or more to reply to the request. This is not actually doing any data edit nor exposing anything; it's just checking whether you're vulnerable.
It's also worth noting that this specifically targets MySQL databases, as the if
and sleep
syntaxes are the ones of that db engine.
If the attack is isolated, you were probably "probed" by an automated vulnerability scanner that is preparing a large-scale attack, so if your webapp is not vulnerable you have nothing to worry about.
However, if you recieve more weird requests with different attack patterns, you could be the specific target of those attackers, and should take actions to prevent all attacks that may succeed.
See Time-Based Blind SQL Injection Attacks for more information.
if(now()=sysdate(),sleep(10),0)/*'XOR(if(now()=sysdate(),sleep(10),0))OR'"XOR(if(now()=sysdate(),sleep(10),0))OR"*/
I found something similar in my db after a huge attack that virtually destroyed my website. Things are fixed now but the damage was big. Security is a priority for us now.