CVE-2002-1520 in Rapidstream
Summary
by MITRE
The CLI interface for WatchGuard Firebox Vclass 3.2 and earlier, and RSSA Appliance 3.0.2, does not properly close the SSH connection when a -N option is provided during authentication, which allows remote attackers to access CLI with administrator privileges.
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Analysis
by VulDB Data Team • 06/13/2018
The vulnerability described in CVE-2002-1520 represents a critical security flaw in the command line interface implementation of WatchGuard Firebox Vclass 3.2 and earlier versions, as well as RSSA Appliance 3.0.2. This issue stems from improper handling of SSH connections during the authentication process, specifically when the -N option is utilized. The flaw allows remote attackers to escalate their privileges and gain administrative access to the system through what should be a secure authentication mechanism. The vulnerability is particularly concerning as it directly impacts the integrity and confidentiality of network security appliances that rely on SSH for remote management and administration.
The technical root cause of this vulnerability lies in the improper closure of SSH connections when the -N option is specified during authentication. This option typically prevents the execution of remote commands and is designed to maintain an interactive session for tunneling purposes. However, in the affected WatchGuard appliances, the system fails to properly terminate or manage these connections, creating a persistent access vector that attackers can exploit. The flaw falls under CWE-284, which addresses improper access control, and specifically relates to inadequate privilege management during authentication processes. When an attacker provides the -N option during SSH authentication, the system does not properly validate or close the connection, leaving the authenticated session in an insecure state that can be leveraged for administrative access.
The operational impact of this vulnerability is severe and multifaceted for organizations using affected WatchGuard appliances. Remote attackers who can establish an SSH connection to the appliance can potentially gain full administrative privileges without proper authorization, leading to complete compromise of the network security infrastructure. This access allows threat actors to modify firewall rules, disable security features, access sensitive network data, and potentially use the compromised appliance as a pivot point for further attacks within the network. The vulnerability essentially undermines the fundamental security model of the appliance, transforming what should be a controlled administrative interface into an open backdoor. According to ATT&CK framework, this vulnerability maps to T1078 - Valid Accounts and T1566 - Phishing, as it enables attackers to leverage legitimate administrative access through compromised authentication mechanisms.
Organizations affected by this vulnerability should implement immediate mitigations including upgrading to patched versions of the WatchGuard software, as the vendor would have released updates addressing the improper SSH connection handling. Network administrators should also consider implementing additional security controls such as restricting SSH access to specific IP addresses, implementing multi-factor authentication, and monitoring SSH connection logs for suspicious activity. The vulnerability highlights the importance of proper resource management and connection handling in security appliances, particularly when dealing with authentication and privilege escalation mechanisms. Additionally, organizations should conduct thorough security assessments of their network infrastructure to identify any other potentially vulnerable appliances or systems that may be subject to similar connection handling flaws, ensuring comprehensive protection against exploitation of such critical access control vulnerabilities.