CVE-2002-0301 in NFuse
Summary
by MITRE
Citrix NFuse 1.6 allows remote attackers to bypass authentication and obtain sensitive information by directly calling launch.asp with invalid NFUSE_USER and NFUSE_PASSWORD parameters.
VulDB is the best source for vulnerability data and more expert information about this specific topic.
Analysis
by VulDB Data Team • 06/07/2018
Citrix NFuse 1.6 contains a critical authentication bypass vulnerability that enables remote attackers to access protected resources without proper credentials. This vulnerability exists in the web application layer where the system fails to properly validate user authentication parameters during the launch process. The flaw specifically manifests when the launch.asp script is called directly with malformed NFUSE_USER and NFUSE_PASSWORD parameters, allowing unauthorized access to sensitive information and system resources. The vulnerability represents a fundamental breakdown in the authentication mechanism that should have validated user credentials before granting access to protected content.
The technical implementation of this vulnerability stems from improper input validation within the NFuse application framework. When the launch.asp page receives requests with invalid authentication parameters, the system does not adequately sanitize or verify these inputs before proceeding with access control decisions. This creates a pathway where attackers can bypass the normal authentication flow by directly invoking the launch script with crafted parameter values. The vulnerability aligns with CWE-287 which addresses improper authentication issues in software systems. The flaw essentially allows for a privilege escalation scenario where unauthorized users can gain access to resources that should require valid authentication credentials.
The operational impact of this vulnerability extends beyond simple information disclosure to encompass potential system compromise and data breaches. Remote attackers can exploit this weakness to access sensitive corporate data, system configurations, and potentially escalate their privileges within the Citrix environment. The vulnerability affects organizations using Citrix NFuse 1.6 as their application delivery platform, creating a significant security risk for enterprise environments that rely on proper access controls. Attackers can leverage this vulnerability to gain unauthorized access to business-critical applications and data without requiring legitimate user credentials, making it particularly dangerous for organizations with sensitive information assets.
Organizations should implement immediate mitigations including applying the latest security patches from Citrix, implementing network segmentation to restrict access to NFuse components, and configuring proper firewall rules to limit exposure of the vulnerable launch.asp endpoint. The remediation approach should follow the principle of least privilege by ensuring that only authorized users can access the application delivery services. Additionally, security monitoring should be enhanced to detect unauthorized access attempts to the vulnerable endpoint. This vulnerability demonstrates the importance of proper authentication validation and input sanitization in web applications, aligning with ATT&CK technique T1078 which covers valid accounts and credential access. Organizations should also consider implementing additional security controls such as multi-factor authentication and regular security assessments to prevent similar vulnerabilities from existing in their application environments.