CVE-2002-0606 in 3Cdaemon
Summary
by MITRE
Buffer overflow in 3Cdaemon 2.0 FTP server allows remote attackers to cause a denial of service (crash) and possibly execute arbitrary code via long commands such as login.
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Analysis
by VulDB Data Team • 09/15/2025
The CVE-2002-0606 vulnerability represents a critical buffer overflow flaw in the 3Cdaemon 2.0 FTP server implementation that fundamentally compromises system stability and security. This vulnerability specifically targets the authentication handling mechanism of the FTP server, where the software fails to properly validate input length during command processing. The flaw manifests when remote attackers submit excessively long commands, particularly login commands, which exceed the allocated buffer space. The vulnerability stems from inadequate bounds checking and memory management practices within the server's command parsing routines, creating an exploitable condition that can be leveraged by malicious actors to disrupt service availability and potentially gain unauthorized system access.
The technical exploitation of this buffer overflow vulnerability follows a well-established pattern that aligns with common software security weaknesses classified under CWE-121. The 3Cdaemon 2.0 server processes user commands without implementing proper input sanitization, allowing attackers to overflow the designated memory buffer and overwrite adjacent memory locations. When the login command exceeds the buffer capacity, the overflow can overwrite return addresses and execution pointers, enabling attackers to redirect program execution flow. This type of vulnerability directly maps to ATT&CK technique T1203, which involves exploiting weaknesses in input validation to achieve arbitrary code execution. The vulnerability's impact extends beyond simple denial of service, as successful exploitation can result in complete system compromise, making it a significant concern for organizations relying on this particular FTP server implementation.
The operational impact of CVE-2002-0606 presents severe consequences for affected systems and network infrastructure. Organizations utilizing 3Cdaemon 2.0 FTP servers face immediate risks including system crashes, service interruptions, and potential unauthorized access to sensitive data repositories. The vulnerability's remote exploitability means that attackers can target systems from outside the network perimeter without requiring local access or authentication. This characteristic transforms what might initially appear as a denial of service vulnerability into a more dangerous threat vector capable of enabling broader compromise. Network administrators must consider the cascading effects of such vulnerabilities, as FTP servers often serve as entry points for lateral movement within corporate networks and may provide access to critical business systems and data storage resources.
Mitigation strategies for CVE-2002-0606 require immediate action to address the underlying buffer overflow condition through comprehensive system hardening measures. Organizations should prioritize upgrading to patched versions of the 3Cdaemon software or migrating to more modern and secure FTP server implementations that properly implement input validation and memory management controls. The implementation of network segmentation and access control measures can help limit the potential impact of exploitation attempts, while regular security audits and vulnerability assessments should be conducted to identify similar weaknesses in other network services. Additionally, deploying intrusion detection systems capable of identifying suspicious command sequences and implementing strict input validation policies for all network services can significantly reduce the attack surface and prevent exploitation of similar buffer overflow vulnerabilities. System administrators should also consider implementing automated patch management processes to ensure timely deployment of security updates and maintain comprehensive monitoring of system logs for signs of exploitation attempts.