CVE-2004-0277 in Dream FTP Server
Summary
by MITRE
Format string vulnerability in Dream FTP 1.02 allows remote attackers to cause a denial of service (crash) and possibly execute arbitrary code via format string specifiers in the username.
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Analysis
by VulDB Data Team • 07/13/2025
The vulnerability identified as CVE-2004-0277 represents a critical format string flaw in Dream FTP Server version 1.02 that exposes the software to remote exploitation. This type of vulnerability occurs when an application improperly handles user-supplied input during format string operations, creating opportunities for attackers to manipulate program execution flow. The specific flaw exists within the username handling mechanism of the FTP server implementation, where the application fails to properly validate or sanitize input before using it in printf-style functions.
The technical nature of this vulnerability places it under CWE-134, which specifically addresses the use of format strings in a manner that allows arbitrary code execution. When attackers supply specially crafted format specifiers in the username field during authentication attempts, the server processes these inputs without proper sanitization, leading to potential stack corruption and arbitrary code execution. The vulnerability is particularly dangerous because it can be exploited during the initial connection phase, meaning attackers can compromise the system before legitimate users can establish sessions.
From an operational perspective, this vulnerability creates a severe risk of denial of service conditions that can crash the entire FTP service, rendering it unavailable to legitimate users and potentially disrupting business operations. The possibility of arbitrary code execution extends the threat beyond simple service disruption, allowing attackers to gain full control over the affected system. This makes the vulnerability particularly attractive to malicious actors seeking persistent access to network infrastructure, as it provides a direct pathway for system compromise and potential lateral movement within the network environment.
The attack surface for this vulnerability is relatively narrow but impactful, as it requires only a basic FTP connection attempt with malicious input. However, the implications are significant given that FTP servers often run with elevated privileges and may be accessible from untrusted networks. Mitigation strategies should include immediate patching of the Dream FTP Server to version 1.03 or later, which addresses the format string vulnerability through proper input validation. Organizations should also implement network segmentation to limit FTP service exposure, deploy intrusion detection systems to monitor for suspicious login patterns, and consider disabling FTP services where possible in favor of more secure alternatives such as SFTP or FTPS protocols. Additionally, implementing proper input validation and sanitization practices in all applications can prevent similar vulnerabilities from occurring in other software components, aligning with ATT&CK technique T1190 for exploitation of vulnerabilities and T1059 for command execution.