Attack Chain

1. An unauthenticated attacker identifies an MGB OpenSource Guestbook 0.7.0.2 installation.
2. The attacker crafts a malicious SQL injection payload.
3. The attacker sends a GET request to email.php with the crafted SQL payload within the id parameter.
4. The email.php script processes the request without proper sanitization of the id parameter.
5. The injected SQL code is executed against the guestbook database.
6. The attacker retrieves sensitive database information, such as table names and column names.
7. The attacker may further exploit the SQL injection to extract user data or modify database contents.
8. The attacker gains unauthorized access to sensitive information or control over the guestbook application.

Impact

Successful exploitation of CVE-2018-25411 can lead to unauthorized access to sensitive database information. This could include user credentials, personal details, or other confidential data stored within the MGB OpenSource Guestbook database. The number of affected installations is unknown. Sectors using this guestbook software are potentially vulnerable. A successful attack could result in data breaches, identity theft, or further compromise of the web server.

Recommendation

• Apply available patches or upgrades to MGB OpenSource Guestbook to address CVE-2018-25411 if available from the vendor.
• Implement input validation and sanitization on the id parameter in email.php to prevent SQL injection attacks.
• Deploy the Sigma rule Detect MGB OpenSource Guestbook SQL Injection via email.php to detect exploitation attempts.
• Monitor web server logs for suspicious GET requests to email.php containing SQL injection payloads.
• Restrict access to the database server from the web server to only necessary accounts and privileges.