Sql Injection Challenge 5 Security Shepherd < PROVEN · EDITION >

OWASP Security Shepherd's SQL Injection Challenge 5 focuses on Boolean-based Blind SQL Injection, requiring users to extract hidden data by inputting TRUE/FALSE queries to infer information. Attackers exploit this by analyzing application responses to guess characters one-by-one using SQL functions like SUBSTRING()

OWASP Security Shepherd's SQL Injection Challenge 5, or "VIP Coupon Check," demonstrates how unsanitized input concatenated directly into database queries creates critical SQL injection vulnerabilities. Attackers can bypass input validation using ' OR '1'='1 or utilize UNION SELECT statements to extract hidden data from the backend. For a detailed walkthrough of this specific challenge, visit this Numerade article. SqlInjection5VipCheck.java - GitHub

The paper you're referring to is likely a write-up or solution guide for SQL Injection Challenge 5 from the OWASP Security Shepherd project.

Security Shepherd is a web app security training platform, and Challenge 5 typically focuses on advanced blind SQL injection or bypassing filters (e.g., stripping spaces, comments, or certain keywords).

Part 4: Manual Exploitation – Thinking Like a Hacker

Let's simulate your first attack on Challenge 5. Assume the target parameter is ?user=5 and the responses are "Valid" (true) or "Invalid" (false).

Conclusion

Security Shepherd SQL Injection Challenge 5 bridges the gap between basic authentication bypass and full data exfiltration. It teaches the attacker to:

Identify that the vulnerability exists despite silent error handling.
Enumerate the database structure (column counts).
Leverage UNION SELECT to force

SQL Injection Challenge 5 in OWASP Security Shepherd is a classic lesson in blind injection and authentication bypass. It tests your ability to manipulate database queries when the application doesn't return direct data. 🛡️ Understanding the Challenge

In Challenge 5, you are typically presented with a login screen or a search bar. Unlike earlier levels where you might see database errors or dumped tables, this level is "quieter." Sql Injection Challenge 5 Security Shepherd

The Goal: Gain unauthorized access or retrieve the hidden "key."

The Vulnerability: The application takes user input and places it directly into a SQL string without sanitization. 🔍 Step-by-Step Walkthrough 1. Identify the Entry Point

Locate the input field. Start by entering a single quote (').

If the page breaks or behaves differently, it confirms the input isn't being escaped.

In Challenge 5, a successful injection often results in a "Welcome" message or a successful login redirect. 2. The Logic Bypass

The query behind the scenes likely looks like this:SELECT * FROM users WHERE username = '$user' AND password = '$pass'

To bypass this, you need to make the WHERE clause always evaluate to TRUE. Enter this into the username field:admin' OR '1'='1 3. Handling the Password OWASP Security Shepherd's SQL Injection Challenge 5 focuses

Since the password check follows the username, you need to "comment out" the rest of the query so the system ignores the password requirement. For MySQL/PostgreSQL: admin' OR '1'='1' # For MS SQL: admin' OR '1'='1' -- 4. Refining the Payload

If the simple bypass doesn't work, the application might be checking for a specific number of columns or a specific user ID. Try:' OR 1=1 LIMIT 1 --

This tells the database: "Give me the first record in the table where the condition is true." Since '1=1' is always true, it logs you in as the first user (usually the Admin). 💡 Key Takeaways for Security Shepherd

Case Sensitivity: Sometimes the keyword OR must be uppercase or lowercase depending on the filter.

URL Encoding: If you are submitting via a URL bar, remember that spaces should be %20 and hashes should be %23.

Observation: Pay attention to the URL or the session tokens after a "successful" login; the key is often hidden there. 🚫 How to Prevent This To stop SQL injection in real-world apps:

Prepared Statements: Use parameterized queries so input is never treated as code. Part 4: Manual Exploitation – Thinking Like a

Input Validation: Use allow-lists to ensure only expected characters are submitted.

Principle of Least Privilege: Ensure the database user has limited permissions.

To help you get through this specific level, could you tell me: What response do you get when you submit a single quote? Are you seeing a login box or a search field?

OWASP Security Shepherd SQL Injection Challenge 5 demonstrates how improper user input handling in database queries allows for unauthorized data access through dynamic SQL construction. The exercise highlights that using parameterized queries, rather than string concatenation, is the primary defense to prevent manipulating database logic [1].

For more information, visit the OWASP Security Shepherd project page.

SQL Injection Challenge 5 in OWASP Security Shepherd involves exploiting a vulnerable coupon code input field to retrieve a VIP code via UNION-based SQL injection. The challenge, which stems from unsanitized user input in a SELECT query, requires injecting payloads like ' UNION SELECT coupon_code FROM coupons WHERE '1'='1

to bypass payment and retrieve the result key. For more details, visit Pentest-Tools.com

Troubleshooting Common Sticking Points

My Union shows numbers but not strings: The columns you are injecting into might be integer types. Cast your string: SELECT CAST(column_name AS CHAR).
The page truncates results: Use group_concat() to combine multiple rows into one.
The challenge says "Try harder": Check for URL encoding. A # in a URL fragment stops the request. Use %23 instead of # for comments.

Typical attack approaches for this challenge

Reconnaissance
- Identify injectable parameters by injecting simple probes:
  - Append "' OR '1'='1" or "' AND '1'='2" and observe any differences.
  - If visible content doesn’t change, try conditional responses (e.g., check presence/absence of specific page text) or timing delays.
Boolean-based blind SQLi
- Use payloads that evaluate true/false and observe page differences:
  - Example structure: input' AND (SUBSTRING((SELECT password FROM users WHERE username='admin'),1,1) = 'a')--
  - Iterate character positions and possible characters to reconstruct sensitive fields.
Time-based blind SQLi
- When the app suppresses conditional output, use DB-specific sleep/delay functions to infer true conditions:
  - For MySQL: input' AND IF(ASCII(SUBSTRING((SELECT password FROM users WHERE username='admin'),1,1)) > 100, SLEEP(5), 0)--
  - Measure response time to deduce bits/characters.
Optimizations
- Binary search on character codes to reduce queries.
- Extract data in chunks (e.g., use SUBSTRING and iterate positions) or extract hashes first, then crack offline.
- Use automated tools (sqlmap) carefully, but manual understanding is important for learning.

Step 1: Find length

for length in range(1, 100): payload = f"(SELECT LENGTH(column_name) FROM table_name WHERE row_condition) = length" if test_payload(payload): print(f"[+] Key length: length") key_length = length break