CVE-2007-4316 in Zywall 2
Summary
by MITRE
The management interface in ZyNOS firmware 3.62(WK.6) on the Zyxel Zywall 2 device has a certain default password, which allows remote attackers to perform administrative actions.
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Analysis
by VulDB Data Team • 11/02/2017
The vulnerability described in CVE-2007-4316 represents a critical authentication flaw within the ZyNOS firmware version 3.62(WK.6) running on Zyxel Zywall 2 network security devices. This issue stems from the implementation of a default password in the management interface, which creates an inherent security weakness that persists even after device deployment and configuration. The presence of hardcoded credentials in network infrastructure devices has long been recognized as a significant risk vector within cybersecurity frameworks, particularly when these credentials remain unchanged throughout the device lifecycle.
The technical nature of this vulnerability falls under CWE-798, which specifically addresses the use of hard-coded credentials in software systems. The flaw allows remote attackers to gain administrative access to the device without requiring any additional authentication mechanisms or credentials to be discovered through network scanning or other reconnaissance techniques. This represents a fundamental failure in the principle of least privilege and proper access control implementation, as the device provides unauthorized users with full administrative capabilities through a simple default credential that is widely known and documented within security communities.
The operational impact of this vulnerability extends far beyond the immediate compromise of a single device. When an attacker successfully exploits this weakness, they gain complete control over the network firewall's configuration, enabling them to modify firewall rules, disable security features, redirect traffic, and potentially establish backdoors for persistent access. This administrative access capability directly violates the security model of network firewalls, which are designed to protect network perimeters and control traffic flow. The attack surface expands significantly as the compromised device can serve as a pivot point for lateral movement within the network infrastructure, allowing attackers to target internal systems that may otherwise be protected by the firewall's security policies.
The implications of this vulnerability align with several tactics outlined in the MITRE ATT&CK framework, particularly those related to initial access through default credentials and privilege escalation. The use of default passwords represents one of the most common attack vectors in network security, as these credentials are often well-documented and readily available in public security databases and exploit frameworks. Organizations deploying network security devices must understand that default credentials pose a persistent risk that can be exploited by both sophisticated attackers and automated scanning tools, making proper credential management and device hardening essential security practices.
Mitigation strategies for this vulnerability require immediate action including immediate credential changes on all affected devices, implementation of strong password policies, and regular security audits to ensure that default configurations have been properly addressed. Network administrators should also implement network segmentation to limit the potential impact of device compromise and establish monitoring procedures to detect unauthorized access attempts. The long-term solution involves ensuring that all network security devices are properly configured with unique, complex credentials during initial deployment and that regular security assessments are conducted to identify and remediate similar vulnerabilities across the entire network infrastructure.