CVE-2000-0220 in ZoneAlarm
Summary
by MITRE
ZoneAlarm sends sensitive system and network information in cleartext to the Zone Labs server if a user requests more information about an event.
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Analysis
by VulDB Data Team • 04/20/2026
The vulnerability identified as CVE-2000-0220 represents a critical security flaw in ZoneAlarm firewall software that exposes sensitive system and network information through unencrypted communication channels. This issue affects the communication protocol between the ZoneAlarm client and Zone Labs servers, where the software transmits diagnostic data and system information without implementing proper encryption mechanisms. The vulnerability specifically manifests when users request additional information about security events, triggering the transmission of potentially sensitive data across networks. This cleartext communication pattern creates significant exposure risks as network traffic can be intercepted and analyzed by malicious actors during transmission.
The technical implementation flaw stems from the absence of secure communication protocols within the ZoneAlarm application's event reporting functionality. When users interact with the software to obtain detailed information about security incidents, the system automatically establishes connections to Zone Labs servers and sends comprehensive system diagnostics including network configurations, system identifiers, and potentially sensitive operational data. The vulnerability operates at the application layer where the software fails to implement encryption standards such as tls or ssl for data transmission, leaving all information vulnerable to eavesdropping attacks. This design oversight directly violates fundamental security principles that require data protection in transit, particularly for applications handling system-level information.
The operational impact of this vulnerability extends beyond simple information disclosure, creating potential pathways for attackers to gain comprehensive insights into target systems and network configurations. An attacker intercepting the cleartext communications could obtain detailed system information including ip addresses, operating system details, network topology information, and potentially sensitive user data that could be leveraged for subsequent attacks. This vulnerability significantly undermines the security posture of organizations relying on ZoneAlarm, as the information transmitted could be used to plan targeted attacks, identify system weaknesses, or facilitate privilege escalation attempts. The exposure affects both individual users and enterprise environments where multiple systems may be transmitting similar diagnostic information.
Mitigation strategies for this vulnerability require immediate implementation of encryption protocols for all client-server communications within the ZoneAlarm application. Organizations should ensure that all system information transmitted to Zone Labs servers is encrypted using established protocols such as tls 1.2 or higher versions. The software vendor must implement proper cryptographic controls that automatically encrypt all diagnostic data before transmission, eliminating the cleartext exposure entirely. Network administrators should monitor for any unauthorized access attempts or unusual network traffic patterns that might indicate exploitation of this vulnerability. Additionally, users should be educated about the risks associated with requesting detailed event information and encouraged to limit such requests to trusted network environments. This vulnerability aligns with CWE-319, which specifically addresses the exposure of sensitive information through cleartext communication, and represents a clear violation of ATT&CK technique T1041, which covers data from network connections and channels. The remediation efforts must include comprehensive security testing to verify that all communication channels are properly encrypted and that no additional cleartext transmissions occur during normal operation.