This is where the subtlety of the challenge lies. If a user attempts a classic SQL injection attack, such as typing 1' OR 1=1; -- , the single quote will be escaped. The query effectively becomes 1\' OR 1=1; -- , which may not execute as intended or could cause an SQL error, as the escaped quote is treated as a literal character rather than a string delimiter.
IF(..., SLEEP(5), 0) : If the character is indeed 'a', the server sleeps for 5 seconds. If it is not, it returns a 0 instantly.
The request will look something like this:
Input: ' OR '1'='1
OWASP Security Shepherd SQL Injection Challenge 5 is an excellent exercise for shifting your mindset from basic web exploitation to structured logical inference. By understanding how backend databases handle logic operators under blind conditions, developers can better appreciate why minor coding oversights result in severe data exposure. Implementing parameterized queries completely neutralizes this attack vector, ensuring your software architecture remains resilient against automated threat vectors. Sql Injection Challenge 5 Security Shepherd
If you attempt a payload like admin' , the application turns it into admin\' , which often results in a "User not found" error because the database is literally searching for a user named admin' . Solving the Challenge: Step-by-Step 1. Analyze the Input and Behavior
Now, if the developer does not sanitize input, an attacker can inject logic:
OWASP Security Shepherd's SQL Injection Challenge 5 is a cleverly designed exercise that teaches a crucial lesson: security is only as strong as its weakest link. A developer might feel safe after escaping single quotes, but a vulnerability in the form of double quotes can undo all that protection.
5' AND '1'='2
Imagine the backend PHP/Node code looks something like this (simplified):
By utilizing greater-than ( > ) or less-than ( < ) operators rather than absolute equals ( = ), you can perform a . This drastically cuts down the number of HTTP requests required to find the correct ASCII value of each character in the flag. Automation: Speeding Up the Process with SQLMap
Suggested mitigations
--technique=T forces SQLMap to strictly use Time-Based blind injection, saving you hours of manual script configuration. Remediation: How to Secure the Code This is where the subtlety of the challenge lies
You need to find which table holds the key. Blindly guess common names like keys , secrets , hash . Using a Boolean condition:
This is the gold standard for SQL injection prevention. Parameterized queries separate SQL logic from data, ensuring that user input is treated as data only, never as executable code.
: The application likely uses a basic SQL query to verify coupons, such as: SELECT coupon_code FROM coupons WHERE coupon_code = 'User_Input';