My First Blog CTF Challenge Writeup

Challenge Information

• Name: My First Blog
• Points: 1
• Category: Web
• Objective: Exploit an SQL injection vulnerability to retrieve admin credentials and obtain the flag.

Solution

To solve the “My First Blog” challenge, follow these steps:

1. Identifying the Vulnerability:

   • The challenge hints at an SQL injection vulnerability.
   • Direct use of SQLmap is not possible, so manual enumeration is necessary.

2. Initial Enumeration:

   • Perform basic enumeration to identify potential SQL errors and found that it might be an SQLite database

     

3. SQL Injection Exploration:

   • Test for SQL injection vulnerabilities by injecting payloads into input fields or URL parameters.

   • Use basic UNION-based SQL injection techniques to determine the number of columns in the SQL queries.

     

     

4. Finding Tables:

   • Once the number of columns is identified, proceed with UNION-based queries to list tables.

   • Identify a table named users.

     

5. Enumerating Columns:

   • Enumerate the columns in the users table to find useful information.

   • Identify columns such as id, username, password, email, and role.

     

6. Retrieving Admin Credentials:

   • Extract the credentials of the admin user from the users table.
   • Use SQL injection to retrieve and view the admin credentials.

7. Flag Retrieval:

   • Submit the retrieved admin credentials as the flag in the format FSIIECTF{XXXXXXXXXX}.