How to remediate – Emerson SM-Ethernet Web Interface Default Credentials

1. Introduction

The Emerson SM-Ethernet Web Interface Default Credentials vulnerability allows unauthorized access to the web application due to the use of default login credentials. This can allow a remote attacker to gain administrative control over affected devices, potentially leading to system compromise and data breaches. Systems commonly affected are Emerson SM-Ethernet modules used in industrial automation environments. A successful exploit could result in loss of confidentiality, integrity, and availability of the controlled systems.

2. Technical Explanation

The vulnerability stems from using default credentials for accessing the web interface of Emerson SM-Ethernet modules. An attacker can log into the device without needing valid user credentials. This is a common misconfiguration that exposes devices to remote exploitation. The Nessus ID 9a30d3f7 provides further details on this issue.

• Root cause: Use of default username and password for web interface access.
• Exploit mechanism: An attacker attempts to log into the web interface using default credentials, typically ‘admin’ as both username and password. If successful, they gain administrative control. For example, an attacker could use a simple script or browser-based login attempt with these defaults.
• Scope: Emerson SM-Ethernet modules are affected. Specific versions were not provided in the context.

3. Detection and Assessment

To confirm vulnerability, check if default credentials allow access to the web interface. A quick check involves attempting a login with ‘admin’ as both username and password. More thorough assessment can be done via network scanning.

• Quick checks: Attempt to log into the web interface using the username “admin” and password “admin”.
• Scanning: Nessus vulnerability scan ID 9a30d3f7 may identify vulnerable devices. Other scanners with similar signatures can also be used as examples only.
• Logs and evidence: Check web server logs for successful login attempts using default credentials, if logging is enabled on the device.

# No command provided in context. Attempt to access the web interface via a browser.

4. Solution / Remediation Steps

To fix this issue, change the default password or block access to the port used by the web interface.

4.1 Preparation

• Services: No services need to be stopped for this remediation.

4.2 Implementation

1. Step 1: Log into the Emerson SM-Ethernet web interface using existing credentials (if known). If unknown, attempt default credentials as a last resort for assessment only.
2. Step 2: Navigate to the user management or password settings section of the web interface.
3. Step 3: Change the default password to a strong, unique password.
4. Step 4: Save the changes and verify that you can log in with the new credentials.

4.3 Config or Code Example

Before

# Default username: admin
# Default password: admin

After

# Username: [Your Chosen Username]
# Password: [Your Strong Password]

4.4 Security Practices Relevant to This Vulnerability

Several security practices can help prevent this type of issue. Least privilege reduces the impact if an account is compromised. Safe defaults ensure systems start in a secure state.

• Practice 1: Implement least privilege access control to limit user permissions and reduce potential damage from compromised accounts.
• Practice 2: Enforce strong password policies, including complexity requirements and regular password changes.

4.5 Automation (Optional)

No automation script is provided in the context.

5. Verification / Validation

• Post-fix check: Attempt to log in with username “admin” and password “admin”. Expected output: Login failure.
• Re-test: Repeat the quick checks from section 3 using default credentials; it should now fail.
• Smoke test: Verify that you can still access the web interface and manage device settings with the new credentials.
• Monitoring: Monitor logs for failed login attempts using default credentials, which could indicate ongoing attacks.

# No command provided in context. Attempt to access the web interface via a browser.

6. Preventive Measures and Monitoring

Update security baselines to include strong password requirements for all devices. Implement regular patch cycles to address known vulnerabilities.

• Baselines: Update your security baseline or policy to require changing default passwords on all new devices.
• Pipelines: Include checks in CI/CD pipelines to ensure that default credentials are not present in configuration files.
• Asset and patch process: Implement a regular patch review cycle for all industrial automation assets.

7. Risks, Side Effects, and Roll Back

8. References and Resources

Links to resources related to this vulnerability.

• Vendor advisory or bulletin: Not provided in context.
• NVD or CVE entry: Not provided in context.
• Product or platform documentation relevant to the fix: Not provided in context.