Top Internal Network Vulnerability Exposures and How to Mitigate Them

In today’s interconnected healthcare landscape, organizations face a multitude of challenges when it comes to securing their internal networks. From insider threats and weak access controls to misconfigurations and outdated software, internal vulnerabilities can expose sensitive data and jeopardize the integrity of an entire organization.

Earlier this year, we once again saw just how impactful the issue can be as a medical device and technology solution vendor notified over 1 million patients who used or were considered for use of the vendor’s product that their data was potentially exposed after a hack of the vendor’s internal network.

Drawing upon our experience in the field supporting hundreds of clients across the healthcare ecosystem, Clearwater’s team of expert cybersecurity professionals is sharing the most common internal network vulnerabilities, offering practical advice, and providing best practices to mitigate them. This blog explores the top 5 internal network vulnerabilities we encounter and outlines actionable steps to address and mitigate these risks.

  1. Using Default Credentials on Internal Web Applications:
    • Exploitation: Attackers attempt to log in to internal web applications using default or weak credentials provided by the application vendor.
    • Impact: Unauthorized access to sensitive information, data manipulation, unauthorized configuration changes, or potential compromise of the entire system.
    • Prevention:
      • Change default credentials immediately after deployment.
      • Implement a robust password policy that mandates strong, unique passwords for all accounts.
      • Utilize strong authentication methods such as multi-factor authentication (MFA) or two-factor authentication (2FA).
      • Regularly review and update credentials, including passwords and access privileges.
      • Conduct periodic security assessments and vulnerability scans to identify and remediate default credential vulnerabilities.
      • Educate users about the importance of choosing strong passwords and not reusing them across multiple accounts.
  2. Weak Password Policies:
    • Exploitation: Attackers exploit weak passwords or common password patterns to gain unauthorized access to user accounts or systems.
    • Impact: Unauthorized access to sensitive data, potential data breaches, identity theft, or compromise of critical systems.
    • Prevention:
      • Implement strong password requirements, including minimum length, complexity, and a combination of alphanumeric and special characters.
      • Educate users about the importance of choosing unique, complex passwords and avoiding common patterns or easily guessable information.
      • Utilize password strength assessment tools or libraries to enforce password complexity during creation or changes.
      • Implement multi-factor authentication (MFA) or two-factor authentication (2FA) for an additional layer of security.
  3. Leveraging LDAP and SMB Signing That Has not Been Enabled:
    • Exploitation: Attackers intercept and manipulate LDAP (Lightweight Directory Access Protocol) and SMB (Server Message Block) traffic, gaining unauthorized access, tampering with data, or delivering malicious payloads undetected.
    • Impact: Compromise of authentication credentials, unauthorized access to sensitive data, potential privilege escalation, or impersonation attacks.
    • Prevention:
      • Enable SMB Signing to ensure the integrity and authenticity of SMB communication.
      • Configure SMB servers and clients to enforce secure SMB connections using digitally signed communications.
      • Implement network segmentation to limit the scope of SMB traffic and isolate critical systems from potential attacks.
      • Regularly patch and update operating systems and SMB implementations to address known vulnerabilities.
      • Enable LDAP Signing to ensure the integrity and authenticity of LDAP communication.
      • Configure LDAP servers and clients to enforce secure LDAP connections using SSL/TLS encryption.
      • Regularly monitor LDAP logs and implement intrusion detection systems to identify and respond to suspicious activities.
  4. Insecure Protocol Deployment:
    • Exploitation: Attackers can intercept and capture data transmitted over insecure protocols, leading to unauthorized access or data compromise. Even though these protocols are deployed within an internal network segment, defaulting to the secure alternatives is an easy way to provide a stronger defense if a security event occurs.
    • Impact: Exposure of sensitive information, potential data breaches, unauthorized system access, or unauthorized modification of data.
    • Prevention:
      • Replace insecure protocols with secure alternatives such as SFTP (Secure File Transfer Protocol) or SSH (Secure Shell) for remote file transfers.
      • Use encrypted protocols such as HTTPS (Hypertext Transfer Protocol Secure) instead of HTTP for web communications.
      • Disable or restrict the use of insecure protocols like FTP and Telnet on critical systems.
      • Regularly update and patch protocols to ensure the latest security enhancements are in place.
      • Conduct regular vulnerability assessments to identify and address any instances of insecure protocol usage.
  5. Weak SSH Implementations
    • Exploitation: Attackers exploit weak SSH configurations, such as weak authentication mechanisms or outdated encryption algorithms, using attacks like POODLE or BEAST.
    • Impact: Unauthorized access to systems, compromise of sensitive data, potential privilege escalation, or unauthorized remote control of affected machines.
    • Prevention:
      • Enforce the use of strong SSH authentication methods, such as public-key authentication, rather than relying solely on passwords.
      • Implement strong encryption algorithms for SSH communications, such as AES (Advanced Encryption Standard).
      • Regularly update and patch SSH server software to address any known vulnerabilities.
      • Monitor SSH logs for suspicious activities, such as repeated failed login attempts, and implement intrusion detection systems to alert on potential breaches.
      • Utilize tools like SSH key management systems to manage and rotate SSH keys securely.

Safeguarding networks from potential threats requires ongoing effort. Network segmentation is a critical security discipline that confines risk and isolates sensitive data and data processing. An internal network penetration test validates the levels of controls and configurations that are in place to mitigate an attacker from moving laterally once they have breached an organization.

As changes rapidly occur within healthcare environments, it’s recommended to have an annual third-party validated penetration test. An internal network penetration test will deliver more in-depth findings about your organization that will help identify changes needed in updates and configurations and in longer-term policies and procedures that will elevate the security posture as your organization grows.

There are many types of security validation testing and scope for penetration testing. Clearwater has the experience and expertise in healthcare to deliver the specialized focus to ensure your continued movement toward greater security, compliance, and resiliency.

Our team is here to help if you need guidance or assistance conducting assessments and testing.

Reach out to us at


Sign up to receive our monthly newsletter featuring resources curated specifically to your concerns.

Related Blogs

With Us