CVE-2000-0711 in Navigator
Summary
by MITRE
Netscape Communicator does not properly prevent a ServerSocket object from being created by untrusted entities, which allows remote attackers to create a server on the victim s system via a malicious applet, as demonstrated by Brown Orifice.
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Analysis
by VulDB Data Team • 01/01/2025
The vulnerability identified as CVE-2000-0711 represents a critical security flaw in Netscape Communicator browsers that stems from inadequate sandboxing mechanisms within the Java applet execution environment. This weakness allows malicious applets to bypass the security restrictions designed to prevent untrusted code from creating server socket connections on victim systems. The vulnerability specifically targets the Java security model implementation in Netscape's browser, where the security manager fails to properly validate socket creation requests originating from applets. The flaw enables attackers to exploit the browser's trust model by crafting malicious applets that can establish server sockets on the victim's machine, effectively creating backdoor listening points that can be used for further exploitation.
The technical implementation of this vulnerability involves the exploitation of Java's security manager functionality, which should normally prevent applets from creating server sockets without explicit permission. When a malicious applet attempts to create a ServerSocket object, the security manager should intercept this request and deny it based on the applet's security context. However, the vulnerability in Netscape Communicator's implementation allows the applet to circumvent this protection mechanism, enabling unauthorized server socket creation. This flaw directly relates to CWE-254, which addresses security weaknesses in the implementation of security features, and more specifically to CWE-252, which deals with improper handling of security checks. The vulnerability demonstrates a fundamental failure in the browser's sandboxing architecture where the security boundaries between trusted and untrusted code are improperly enforced.
The operational impact of this vulnerability is severe and far-reaching, as it provides attackers with the capability to establish persistent listening points on compromised systems without requiring elevated privileges. The Brown Orifice demonstration showcased how attackers could leverage this vulnerability to create server sockets that would allow them to receive connections from external hosts, effectively turning compromised user machines into relay points for malicious activities. This capability enables various attack vectors including but not limited to remote command execution, data exfiltration, and the establishment of botnet command and control channels. The vulnerability can be exploited through web-based attacks, where users visiting compromised websites containing malicious applets automatically trigger the exploit without any user interaction beyond normal browsing. The attack surface is particularly concerning because it affects the core browser functionality and leverages the trust model that users implicitly place in their web browsers.
Mitigation strategies for this vulnerability require immediate patching of affected Netscape Communicator versions and implementation of additional security measures to prevent exploitation. Organizations should ensure that all affected browsers are updated to versions containing the security fixes that properly enforce socket creation restrictions. System administrators should consider implementing network-level firewalls and intrusion detection systems to monitor for suspicious server socket activity on user systems. The security model should be enhanced to include additional validation layers that verify the security context of socket creation requests regardless of the calling code's origin. This vulnerability highlights the importance of proper sandboxing implementation and the need for comprehensive security testing of browser security features. From an ATT&CK framework perspective, this vulnerability maps to T1059.007 for command and scripting interpreter and T1071.004 for application layer protocol, as it enables attackers to establish persistent communication channels and execute commands through compromised systems. The vulnerability also demonstrates the critical importance of maintaining up-to-date security patches and the potential consequences of insufficient sandboxing in web browsers.