CVE-2006-4309 in Windows Terminal
Summary
by MITRE
VNC server on the AK-Systems Windows Terminal 1.2.5 ExVLP is not password protected, which allows remote attackers to login and view RDP or Citrix sessions.
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Analysis
by VulDB Data Team • 09/25/2017
The vulnerability described in CVE-2006-4309 represents a critical security flaw in the AK-Systems Windows Terminal 1.2.5 ExVLP software that exposes remote desktop and Citrix sessions to unauthorized access. This issue specifically affects the VNC server component within the terminal software, which fails to implement proper authentication mechanisms. The vulnerability stems from a fundamental design flaw where the VNC server operates without requiring any password verification, creating an open access point that malicious actors can exploit to gain unauthorized access to sensitive desktop environments.
This technical weakness manifests as a complete absence of authentication controls within the VNC server implementation, making it a prime example of a misconfigured security mechanism that violates core security principles. The vulnerability directly maps to CWE-305 authentication bypass, where the system fails to properly verify user credentials before granting access to protected resources. The flaw exists at the application layer where the VNC server component should enforce authentication but instead provides unrestricted access to all session data. The absence of password protection creates a direct pathway for remote attackers to establish connections and view or potentially manipulate active RDP and Citrix sessions without any authorization checks.
The operational impact of this vulnerability is severe and multifaceted, as it enables attackers to perform reconnaissance and potentially execute malicious activities within corporate networks. Remote attackers can leverage this vulnerability to gain visibility into sensitive desktop sessions, potentially accessing confidential data, executing commands, or conducting further attacks within the network perimeter. The exposure of RDP and Citrix sessions creates opportunities for lateral movement, privilege escalation, and data exfiltration. This vulnerability particularly affects enterprise environments where terminal servers and remote access solutions are commonly deployed, making it a significant concern for organizations relying on these technologies for remote access and desktop management.
From a threat modeling perspective, this vulnerability aligns with several ATT&CK techniques including T1071.001 for application layer protocol usage and T1046 for network service scanning. The vulnerability demonstrates a classic security misconfiguration pattern where default settings fail to provide adequate protection. Organizations should implement immediate mitigations including disabling the VNC server component when not actively required, implementing network segmentation to isolate affected systems, and deploying proper access controls. Additionally, regular security assessments should verify that all remote access services properly enforce authentication mechanisms. The vulnerability underscores the critical importance of secure configuration management and the need for organizations to regularly audit their security settings to prevent such exposure scenarios. Organizations should also consider implementing network monitoring solutions to detect unauthorized VNC connections and establish proper incident response procedures for such security events.