How to remediate – QNAP QTS / QuTS Hero Default Credentials

1. Introduction

The QNAP QTS / QuTS Hero Default Credentials vulnerability involves the use of pre-set, well-known usernames and passwords on QNAP network attached storage (NAS) devices running either QTS or QuTS Hero operating systems. This allows attackers to gain unauthorised administrative access to these devices. Successful exploitation could compromise data confidentiality, integrity, and availability.

2. Technical Explanation

The vulnerability stems from hard-coded default credentials within the web administration interface of QNAP NAS devices. An attacker can attempt to log in using these known credentials without needing any prior knowledge of legitimate user accounts. This is a common entry point for attackers targeting internet-exposed NAS systems. There is no specific CVE currently associated with this issue, but it’s related to CWE-798 (Use of Hard-coded Credentials). An attacker could simply enter the default username and password into the login form on the web interface.

• Root cause: The QNAP devices ship with a set of default credentials that are not changed during initial setup.
• Exploit mechanism: An attacker attempts to log in to the web administration interface using the default credentials, typically ‘admin’ for username and ‘admin’ or a blank password for password.
• Scope: QNAP NAS devices running QTS and QuTS Hero operating systems are affected. Specific versions have not been identified as universally vulnerable; this is generally an issue of configuration rather than specific software flaws.

3. Detection and Assessment

You can check if a system is vulnerable by attempting to log in with default credentials. A thorough assessment involves checking all exposed QNAP NAS devices.

• Quick checks: Access the web administration interface of your QNAP device via a web browser, and attempt login using username ‘admin’ and password ‘admin’.
• Scanning: Nessus plugin ID 16829 can identify default credentials on QNAP devices. This is provided as an example only; results may vary depending on scanner configuration.
• Logs and evidence: Check the system logs for failed login attempts using the default username. Log files are typically located in /var/log/auth.log or similar, but location varies by model.

ssh admin@<device_ip_address> 'cat /etc/config/qnap_credentials'

4. Solution / Remediation Steps

The primary solution is to change the default credentials immediately. Follow these steps carefully.

4.1 Preparation

• Ensure you have a documented roll back plan in case of issues. The roll back involves restoring the previous backup.
• A change window may be needed if this impacts users; approval from IT management might be necessary.

4.2 Implementation

1. Step 1: Log in to the QNAP web administration interface using an existing account (if possible). If you can only log in with default credentials, proceed immediately to step 2.
2. Step 2: Navigate to Control Panel > Security > User Management.
3. Step 3: Select the ‘admin’ user and click ‘Modify’.
4. Step 4: Change the password for the ‘admin’ account to a strong, unique password.
5. Step 5: Log out of the web administration interface and log back in using the new credentials.

4.3 Config or Code Example

Before

# Default admin user with default password (example)
admin: $1$abcdefghijklmnopqrstuvwxyz0123456789/somehashvalue

After

# Admin user with a strong, unique password
admin: $1$newstrongpasswordhashvalue

4.4 Security Practices Relevant to This Vulnerability

Several security practices can help prevent this type of issue.

• Practice 1: Least privilege – limit the permissions granted to user accounts, reducing potential damage if compromised.
• Practice 2: Safe defaults – avoid shipping devices with default credentials; force password changes during initial setup.

4.5 Automation (Optional)

Automation is not generally suitable for this vulnerability due to the need for interactive input and device-specific configurations.

5. Verification / Validation

• Post-fix check: Attempt to log in to the web administration interface using username ‘admin’ and password ‘admin’. The login attempt should fail.
• Re-test: Repeat the quick check from section 3; it should no longer be possible to log in with default credentials.
• Monitoring: Check system logs for failed login attempts using the default username. A spike in these events could indicate ongoing attacks.

ssh admin@<device_ip_address> 'cat /etc/config/qnap_credentials'

6. Preventive Measures and Monitoring

Regular security baselines and patch management are important.

• Baselines: Update your security baseline to include a requirement for strong passwords on all QNAP devices, and regular password changes.
• Pipelines: Consider using configuration management tools to enforce password policies across multiple devices.
• Asset and patch process: Implement a regular review cycle (e.g., monthly) to verify that all QNAP NAS devices have strong passwords set.

7. Risks, Side Effects, and Roll Back

Changing the admin password could temporarily disrupt access if forgotten. A roll back is possible by restoring from backup.

• Risk or side effect 1: Forgetting the new password can lock you out of the device; document it securely.
• Roll back: Restore your QNAP NAS configuration from the backup created in step 4.1.

8. References and Resources

Links to official advisories are recommended.

• Vendor advisory or bulletin: QNAP Security Advisory
• NVD or CVE entry: No specific CVE currently exists for this issue, but search the NVD database for QNAP vulnerabilities.
• Product or platform documentation relevant to the fix: QNAP User Management Documentation