CVE-2015-7998 in Netscaler Application Delivery Controller
Summary
by MITRE
The administration UI in Citrix NetScaler Application Delivery Controller (ADC) and NetScaler Gateway before 10.1 Build 133.9, 10.5 before Build 58.11, and 10.5.e before Build 56.1505.e on NetScaler Service Delivery Appliance Service VM (SVM) devices allows attackers to obtain sensitive information via unspecified vectors.
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Analysis
by VulDB Data Team • 05/17/2018
The vulnerability identified as CVE-2015-7998 affects Citrix NetScaler Application Delivery Controller and NetScaler Gateway appliances across multiple software versions including 10.1 Build 133.9 and earlier, 10.5 before Build 58.11, and 10.5.e before Build 56.1505.e on NetScaler Service Delivery Appliance Service VM devices. This issue resides within the administration user interface component of these network security appliances, which are widely deployed for load balancing, application delivery, and secure remote access services. The vulnerability represents a significant security weakness that could enable unauthorized access to critical system information, potentially compromising the entire network infrastructure that relies on these appliances for traffic management and security enforcement.
The technical flaw manifests through unspecified vectors that allow attackers to extract sensitive information from the administration UI of the affected Citrix appliances. This type of information disclosure vulnerability typically occurs when the system fails to properly validate or restrict access to administrative functions, potentially exposing configuration details, credentials, system parameters, or other confidential data through the web-based management interface. The vulnerability exists in the authentication and authorization mechanisms of the administration UI, where proper access controls may be missing or insufficiently implemented, allowing unauthorized users to bypass normal security restrictions and gain access to privileged information.
The operational impact of this vulnerability is substantial for organizations relying on Citrix NetScaler appliances for their network security infrastructure. Attackers who successfully exploit this vulnerability could obtain sensitive information that would enable them to understand the internal network topology, identify system configurations, discover administrative credentials, and potentially escalate their privileges within the appliance. This information disclosure could serve as a foundation for more sophisticated attacks, including privilege escalation, lateral movement within the network, or targeted attacks against other systems that depend on the compromised appliance. The affected appliances are commonly used in enterprise environments for critical traffic management and security functions, making this vulnerability particularly dangerous for organizations that depend on these systems for network access control and application delivery.
Organizations should immediately apply the vendor-provided patches and updates for the affected Citrix NetScaler versions to remediate this vulnerability. The patching process should include updating all affected appliances across the enterprise network, with particular attention to those running the vulnerable software versions mentioned in the CVE description. Security teams should implement network monitoring to detect any suspicious activity that might indicate exploitation attempts, including unusual access patterns to the administration interfaces. Additional mitigations include restricting access to the administration UI through network segmentation, implementing strong access controls and authentication mechanisms, and conducting thorough security assessments of the appliance configurations to ensure that only authorized personnel have access to administrative functions. This vulnerability aligns with CWE-200, which covers information exposure, and represents a potential entry point for attacks categorized under the MITRE ATT&CK framework's credential access and defense evasion tactics, highlighting the importance of maintaining up-to-date security controls and implementing proper network segmentation strategies to limit the potential impact of such vulnerabilities.