CVE-2008-2399 in FireFTP
Summary
by MITRE
Directory traversal vulnerability in the FireFTP add-on before 0.98.20080518 for Firefox allows remote FTP servers to create or overwrite arbitrary files via ..\ (dot dot backslash) sequences in responses to (1) MLSD and (2) LIST commands, a related issue to CVE-2002-1345. NOTE: this can be leveraged for code execution by writing to a Startup folder.
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Analysis
by VulDB Data Team • 11/29/2024
The vulnerability described in CVE-2008-2399 represents a critical directory traversal flaw within the FireFTP Firefox add-on, specifically affecting versions prior to 0.98.20080518. This security weakness stems from inadequate input validation mechanisms within the add-on's handling of FTP server responses, particularly when processing MLSD and LIST command outputs. The flaw enables malicious remote FTP servers to manipulate file creation and overwriting operations through carefully crafted ..\ sequences in server responses, effectively allowing attackers to traverse the file system beyond intended boundaries.
The technical implementation of this vulnerability operates through the manipulation of FTP command responses where the FireFTP add-on fails to properly sanitize or validate directory paths received from remote servers. When the add-on processes MLSD and LIST commands, it does not adequately filter or normalize path sequences containing ..\ patterns, which are standard indicators of directory traversal attempts in various file systems. This processing gap creates an opportunity for remote attackers to specify arbitrary file paths that bypass normal file system access controls, potentially allowing them to write files to locations outside the intended download directories.
The operational impact of this vulnerability extends far beyond simple file system manipulation, as it can be leveraged for complete system compromise through code execution. The vulnerability's potential for exploitation becomes particularly dangerous when attackers can write malicious files to system startup folders, such as the Windows Startup directory or equivalent system initialization locations. This capability transforms the directory traversal vulnerability into a persistent threat that can execute malicious code automatically upon system boot or user login, providing attackers with long-term access to compromised systems.
This vulnerability aligns with CWE-22, which describes improper limitation of a pathname to a restricted directory, commonly known as path traversal or directory traversal. The flaw demonstrates how web and FTP client applications can be exploited through manipulation of server responses, similar to the patterns seen in CVE-2002-1345 which established the foundation for understanding such traversal attacks. The ATT&CK framework categorizes this vulnerability under T1059.007 for Windows Scripting and T1547.001 for Registry Run Keys / Startup Folder, highlighting how attackers can leverage such vulnerabilities to establish persistence mechanisms.
Mitigation strategies for this vulnerability require immediate patching of the FireFTP add-on to version 0.98.20080518 or later, which includes proper input validation and path normalization mechanisms. Organizations should implement network segmentation and access controls to limit FTP server access, particularly from untrusted networks. Additionally, security monitoring should focus on detecting unusual file creation patterns in system directories and startup folders. The remediation process must include comprehensive testing of FTP client configurations and validation of path handling mechanisms within all browser add-ons that interact with remote file systems, ensuring that proper sanitization occurs at all points where external input influences file system operations.