CVE-2006-2172 in G6 FTP Server
Summary
by MITRE
Buffer overflow in Gene6 FTP Server 3.1.0 allows remote authenticated attackers to cause a denial of service (crash) and possibly execute arbitrary code via a long argument to (1) MKD or (2) XMKD, as demonstrated by the Infigo FTPStress Fuzzer.
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Analysis
by VulDB Data Team • 06/17/2019
The vulnerability identified as CVE-2006-2172 represents a critical buffer overflow flaw within Gene6 FTP Server version 3.1.0 that exposes the system to remote authenticated attack vectors. This weakness specifically manifests when the server processes overly long arguments to the MKD (Make Directory) and XMKD (Extended Make Directory) FTP commands, creating a scenario where attacker-controlled input can overwrite adjacent memory locations. The vulnerability operates through a classic stack-based buffer overflow mechanism where insufficient input validation allows maliciously crafted payloads to exceed the allocated buffer space, potentially leading to unpredictable behavior including application crashes or complete system compromise.
The technical exploitation of this vulnerability follows a well-documented pattern that aligns with CWE-121, which categorizes stack-based buffer overflow conditions. When an authenticated user sends a specially crafted command containing an excessively long argument string to either MKD or XMKD functions, the server's input handling routine fails to properly validate the length of the provided data. This validation failure allows the attacker to overwrite stack canaries, return addresses, or other critical memory segments, thereby enabling the potential for arbitrary code execution or system crash. The vulnerability is particularly concerning because it requires only authenticated access, meaning that an attacker who has already established a valid FTP session can leverage this flaw to escalate their privileges or disrupt service availability.
From an operational impact perspective, this vulnerability creates significant risk for organizations relying on Gene6 FTP Server as part of their infrastructure. The potential for remote code execution means that attackers could gain full control over the affected system, potentially leading to data breaches, privilege escalation, or use of the compromised server as a pivot point for further attacks within the network. The denial of service aspect of this vulnerability also presents substantial business risk, as FTP service disruption can impact critical operations and user access. Organizations implementing the affected software may experience system instability, unauthorized access to sensitive data, and potential regulatory compliance violations depending on their industry requirements.
Security professionals should implement immediate mitigations including applying vendor patches or upgrading to newer versions of Gene6 FTP Server that address this buffer overflow condition. Network segmentation and access controls can help limit the potential impact by restricting unauthorized access to the FTP service. Additionally, implementing intrusion detection systems that monitor for suspicious FTP command patterns and conducting regular security assessments can help identify exploitation attempts. The vulnerability demonstrates the importance of input validation and proper memory management practices as outlined in the OWASP Top Ten and MITRE ATT&CK framework, specifically addressing techniques related to command injection and privilege escalation. Organizations should also consider implementing application whitelisting and runtime protection mechanisms to prevent exploitation of similar buffer overflow vulnerabilities in other applications and systems.