CVE-2007-2318 in FileZilla
Summary
by MITRE
Multiple format string vulnerabilities in FileZilla before 2.2.32 allow remote attackers to execute arbitrary code via format string specifiers in (1) FTP server responses or (2) data sent by an FTP server. NOTE: some of these details are obtained from third party information.
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Analysis
by VulDB Data Team • 06/08/2025
The vulnerability identified as CVE-2007-2318 represents a critical format string vulnerability affecting FileZilla versions prior to 2.2.32. This flaw resides in the client-side implementation where the application fails to properly validate and sanitize input data received from FTP servers during both control and data channel communications. The vulnerability manifests when FileZilla processes responses from FTP servers that contain maliciously crafted format string specifiers, creating an avenue for remote code execution attacks. These format string vulnerabilities occur when the application uses user-supplied data directly in printf-style functions without proper sanitization, allowing attackers to manipulate memory layout and potentially execute arbitrary code on the victim's system.
The technical nature of this vulnerability aligns with CWE-134, which specifically addresses the use of format strings without proper validation in software applications. The flaw exists in both FTP server response handling and data channel processing, making it particularly dangerous as attackers can exploit it through multiple vectors. When an FTP server responds with malicious format specifiers, FileZilla's client-side code processes these strings without adequate input validation, leading to potential stack corruption and memory access violations. The vulnerability's impact extends beyond simple data manipulation as it can be leveraged to overwrite critical memory locations, potentially allowing attackers to inject and execute malicious code with the privileges of the FileZilla process. This vulnerability is particularly concerning because it operates at the application layer and can be exploited without requiring authentication or direct network access to the vulnerable system.
The operational impact of CVE-2007-2318 is significant as it enables remote attackers to gain unauthorized code execution capabilities on systems running vulnerable FileZilla clients. Attackers can craft malicious FTP server responses that contain format string specifiers designed to manipulate the client's memory layout and execute arbitrary commands. This vulnerability can be exploited in various attack scenarios including man-in-the-middle attacks where an attacker controls an FTP server, or through compromised legitimate FTP servers that have been modified to include malicious responses. The attack surface is broad as any system using FileZilla for FTP operations becomes vulnerable, particularly in environments where users connect to untrusted FTP servers. The vulnerability's exploitation can lead to complete system compromise, data theft, or further network infiltration, making it a critical security concern for organizations relying on FTP client software.
Mitigation strategies for CVE-2007-2318 primarily focus on immediate software updates and operational security measures. The most effective solution is upgrading to FileZilla version 2.2.32 or later, which includes proper input validation and sanitization of format string parameters. Organizations should implement network segmentation and access controls to limit exposure to untrusted FTP servers, while also monitoring network traffic for suspicious FTP server responses. Security teams should consider implementing network-based intrusion detection systems that can identify and block known malicious FTP response patterns. Additionally, users should be educated about the risks of connecting to untrusted FTP servers and the importance of using secure protocols where possible. The vulnerability's classification under ATT&CK technique T1059.007 (Command and Scripting Interpreter: PowerShell) and T1219 (Remote Access Tools) indicates that exploitation could enable broader attack chains involving lateral movement and persistence mechanisms. Organizations should also consider implementing application whitelisting policies to prevent execution of unauthorized code and maintain regular security assessments to identify and remediate similar vulnerabilities in other software components.