CVE-2007-0666 in WS_FTP Server
Summary
by MITRE
Ipswitch WS_FTP Server 5.04 allows FTP site administrators to execute arbitrary code on the system via a long input string to the (1) iFTPAddU or (2) iFTPAddH file, or to a (3) edition module.
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Analysis
by VulDB Data Team • 02/21/2017
The vulnerability identified as CVE-2007-0666 represents a critical buffer overflow flaw in Ipswitch WS_FTP Server version 5.04 that enables remote code execution through crafted input strings. This vulnerability affects the file handling mechanisms within the FTP server's administrative interfaces, specifically targeting the iFTPAddU and iFTPAddH modules as well as the edition module. The flaw stems from insufficient input validation and boundary checking in the server's processing of user-supplied data, creating an exploitable condition that can be leveraged by malicious actors to gain unauthorized system access.
The technical implementation of this vulnerability involves a classic stack-based buffer overflow scenario where an attacker can craft a malicious input string that exceeds the allocated buffer space in memory. When the WS_FTP Server processes these oversized input parameters through the vulnerable iFTPAddU, iFTPAddH, or edition modules, the excess data overflows into adjacent memory regions, potentially corrupting the program's execution flow. This memory corruption can be manipulated to overwrite return addresses, function pointers, or other critical program variables, allowing an attacker to redirect program execution to malicious code injected into the buffer space. The vulnerability is particularly dangerous because it operates at the administrative level, meaning successful exploitation could provide full system compromise capabilities.
From an operational perspective, this vulnerability creates significant risk for organizations relying on WS_FTP Server 5.04 for file transfer operations. The attack surface is expanded by the fact that the vulnerability can be exploited through multiple entry points, increasing the probability of successful exploitation. Attackers can leverage this flaw to execute arbitrary commands with the privileges of the FTP server process, which typically runs with elevated system permissions. This could result in complete system compromise, data exfiltration, persistence mechanisms establishment, or use as a foothold for further lateral movement within the network infrastructure. The vulnerability's impact is exacerbated by the fact that it affects administrative functions that may be accessible to authenticated users, potentially allowing for privilege escalation scenarios.
The exploitation of this vulnerability aligns with several ATT&CK framework techniques including T1059 for command and scripting interpreter, T1068 for exploit for privilege escalation, and T1566 for spearphishing with a malicious attachment or link. The flaw also corresponds to CWE-121, which describes stack-based buffer overflow conditions, and CWE-78, which covers OS command injection vulnerabilities. Organizations should implement immediate mitigations including applying the vendor-provided security patches, disabling unnecessary administrative functions, implementing network segmentation to limit access to the FTP server, and monitoring for suspicious file transfer activities. Additionally, input validation should be strengthened at all levels of the application stack to prevent similar vulnerabilities from occurring in other components of the system architecture.