Executive Summary
A global Data Intelligence and Asset Management firm partnered with CyberSapiens to identify and remediate critical vulnerabilities in its internal and external network systems. With a focus on uptime, sensitive client data, and compliance-driven operations, the firm required a rigorous security evaluation.
Through a structured VAPT approach, CyberSapiens uncovered high-risk misconfigurations that could allow unauthorized access, denial-of-service (DoS), and user enumeration — all of which were successfully mitigated.
Scope
The assessment covered 40+ critical assets, including:
- Internal Servers – Hosting sensitive business applications and proprietary data.
- External Hosts – Providing access to remote users and integrated services.
Methodologies Used
The evaluation was conducted using industry-standard security frameworks:
- OWASP Testing Guide – Identifying authentication and access control vulnerabilities.
- PTES – Structured assessment from reconnaissance to exploitation.
- NIST Guidelines – Ensuring alignment with best practices for network security.
- CIS Benchmarks – Strengthening system configurations against known threats.
This structured approach ensured comprehensive risk identification and mitigation planning.
Findings
RPC DoS Vulnerability in nix rpcbind/libtirpc
- Vulnerability: CVE-2017-8779
- Impact: Attackers could exploit a flaw in rpcbind, causing a Denial-of-Service and disrupting network operations.
Anonymous Authentication in Active Directory
- Vulnerability: CVE-1999-0519
- Impact: SMB shares were accessible without authentication, exposing sensitive data to unauthorized users.
Null Authentication in rpcclient Utility
- Impact: Attackers could interact with RPC endpoints via named pipes, extracting user and group details to facilitate further attacks.
Impact on the Network Infrastructure
- Service Disruption: Exploitation of the rpcbind vulnerability could result in Denial-of-Service attacks, leading to system downtime.
- Unauthorized Data Access: Weak Active Directory settings allowed unauthenticated access to sensitive SMB shares.
- Privilege Escalation Risks: Attackers could leverage RPC user enumeration to execute lateral movement within the network.
Remediation Steps
To mitigate these risks, the following security measures were recommended:
- Patched rpcbind/libtirpc – Eliminated DoS risk by updating to the latest secure versions.
- Disabled Anonymous SMB Access – Enforced authenticated access to internal file shares.
- Hardened RPC Access – Disabled null authentication and enforced strong user credentials.
Results After Implementing Remediations
- Enhanced Access Security: Unauthorized access to SMB shares was successfully restricted.
- Denial-of-Service Prevention: Patched rpcbind vulnerability eliminated risks of service disruption.
- Stronger Authentication Controls: Anonymous RPC access was eliminated, securing user data and system configurations.
Conclusion
Through this engagement, the client achieved a measurable improvement in their network security posture. Critical vulnerabilities were addressed, and security best practices were implemented — reinforcing the organization’s commitment to data integrity, system availability, and client trust.
