DHS network policy puts systems at risk, IG finds
Stronger security controls needed on Active Directory systems
The Homeland Security Department has allowed information technology systems from some of its component agencies with security vulnerabilities to connect to its network, putting department data at risk, according to DHS Inspector General Richard Skinner.
In a recent performance audit, the IG found that systems from U.S. Customs and Border Protection, Immigrations and Customs Enforcement, and the department’s Science and Technology directorate in DHS’ enterprise application domain had security vulnerabilities and lacked configuration controls that met DHS' guidance. The vulnerabilities included missing security patches, which left servers and the department’s headquarters domain and network at risk, the IG said in a report released June 8.
The issue is how the department has used Microsoft Windows Active Directory services to manage users, groups of users, computer systems, and services on its headquarters’ network.
DHS uses a federated model for Active Directory in which policy and guidance are determined centrally, but DHS agencies are responsible for their own network operations, Skinner said. The department has established "trusts" between its headquarters’ domain and the domains of nine component agencies to give users access to centralized enterprisewide applications, according to the IG. The deployment of enterprise applications on the headquarters domain represents progress toward a department goal laid out in 2007 of achieving a "one DHS" information-sharing environment, the report said.
However, according to Skinner, some systems in DHS’ enterprise Active Directory domain are not fully compliant with the department’s security guidelines, and no mechanism is in place to ensure their security level. Systems from DHS’ components were added to the department's domain before their security configurations were validated, the IG said.
"By accepting trusted systems from other components without enforcing or confirming security controls, DHS exposes its network to vulnerabilities contained on those systems," the report states. "Risks associated with these vulnerabilities include potential unauthorized access to data or interruption of critical services to both DHS employees and the public."
The IG found DHS’ Active Directory structure isn’t optimized for supporting applications across DHS’ enterprise. In addition, Skinner said DHS hasn’t established policy to enforce the placement of security controls on its component systems.
"While DHS continues to speed the deployment of state-of-the-art systems and strive for ‘one DHS’ as directed by the secretary, it cannot sacrifice the confidentiality, integrity, or availability of its data and services," the IG concluded. "DHS’ current Active Directory trusts pose risks and require stronger security controls in place to provide secure and effective enterprise services."
To fix the problem, Skinner recommended that the department:
- Verify security controls are put in place and configuration settings comply with DHS’ policy for systems connected through trusts to the department's Active Directory enterprise application domain.
- Deal with the current vulnerabilities on systems connected to the Active Directory.
- Ensure appropriate security measures are taken for all systems by providing governance.
DHS’ Office of the Chief Information Officer agreed to the three recommendations, and Skinner said his office considers them resolved, but they will remain open until the OCIO shows that all planned corrective steps have been completed.
The performance audit was completed between September 2009 and January 2010.