CVE-2018-14941 in NSG 9000
Summary
by MITRE
Harmonic NSG 9000 devices allow remote authenticated users to read the webapp.py source code via a direct request for the /webapp.py URI.
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Analysis
by VulDB Data Team • 03/13/2020
The vulnerability identified as CVE-2018-14941 affects Harmonic NSG 9000 network security appliances, representing a critical information disclosure flaw that enables remote authenticated attackers to access sensitive application source code. This vulnerability resides within the web application layer of the device, specifically exposing the webapp.py file through an unsecured direct URI request mechanism. The flaw demonstrates a fundamental weakness in the device's access control implementation, where proper authorization checks fail to validate whether authenticated users should have access to underlying application source files.
This vulnerability maps directly to CWE-200, which describes improper exposure of sensitive information, and aligns with ATT&CK technique T1083, Information Discovery, as it allows adversaries to gather detailed information about the target system's software architecture and implementation. The affected device operates with a web-based management interface that fails to properly enforce file access restrictions, creating an attack vector where legitimate authenticated users can leverage their credentials to access not just the application's functionality but also its source code implementation. The webapp.py file likely contains critical business logic, configuration parameters, and potentially hard-coded credentials or cryptographic keys that could be exploited by attackers.
The operational impact of this vulnerability extends beyond simple information disclosure, as the exposed source code provides attackers with detailed insights into the application's internal workings, including potential implementation flaws, data handling procedures, and system architecture patterns. Attackers can analyze the source code to identify additional vulnerabilities, understand the application's communication protocols, and potentially discover other accessible files or directories that may not be properly protected. This information can significantly aid in planning more sophisticated attacks against the device or the broader network infrastructure it protects. The vulnerability affects the device's security posture by undermining the principle of least privilege, where access to source code should be restricted to authorized developers and system administrators only.
Mitigation strategies for this vulnerability should focus on implementing proper input validation and access control mechanisms within the web application layer. Network administrators must ensure that all file access requests are properly authenticated and authorized, with appropriate access controls enforced at the application level rather than relying solely on network-level protections. The device firmware should be updated to the latest version provided by Harmonic, which includes patches addressing the source code disclosure issue. Additionally, implementing web application firewalls and content delivery network protections can help filter malicious requests targeting specific URI patterns. Regular security assessments should include testing for similar information disclosure vulnerabilities, and access to sensitive files should be restricted through proper file permissions and application-level controls. Organizations should also consider implementing network segmentation and monitoring to detect unusual access patterns that might indicate exploitation attempts.