CVE-2012-6664 in Distinct Intranet Servers
Summary
by MITRE • 06/22/2024
Multiple directory traversal vulnerabilities in the TFTP Server in Distinct Intranet Servers 3.10 and earlier allow remote attackers to read or write arbitrary files via a .. (dot dot) in the (1) get or (2) put commands.
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Analysis
by VulDB Data Team • 09/15/2024
The vulnerability identified as CVE-2012-6664 represents a critical directory traversal flaw within the TFTP Server component of Distinct Intranet Servers version 3.10 and earlier. This vulnerability specifically affects the handling of file operations within the Trivial File Transfer Protocol implementation, creating a pathway for remote attackers to manipulate file system access through carefully crafted requests. The flaw exists in the server's interpretation of directory navigation sequences, particularly when processing get and put commands that contain dot-dot sequences.
The technical implementation of this vulnerability stems from inadequate input validation and path sanitization within the TFTP server's file handling mechanisms. When a client sends a get or put command containing .. sequences, the server fails to properly validate or sanitize these path traversal elements, allowing attackers to navigate outside the intended directory structure. This weakness directly maps to CWE-22, which describes improper limitation of a pathname to a restricted directory, commonly known as path traversal or directory traversal attacks. The vulnerability enables attackers to access files outside the designated TFTP root directory, potentially exposing sensitive system files, configuration data, or other protected resources.
The operational impact of this vulnerability is severe and multifaceted, as it provides remote attackers with unauthorized access to the file system of the affected server. Attackers can leverage this flaw to read arbitrary files, potentially including system configuration files, user credentials, or sensitive application data. Additionally, the ability to write files through the put command allows for potential code injection or system compromise. The vulnerability affects both read and write operations, making it particularly dangerous for environments where the TFTP server is used for file distribution or system administration tasks. This exposure could lead to complete system compromise, data theft, or disruption of network services.
Mitigation strategies for CVE-2012-6664 should prioritize immediate patching of the Distinct Intranet Servers software to version 3.11 or later, which contains the necessary security fixes. Organizations should implement network segmentation to limit access to TFTP servers and restrict the number of users with access to these services. The principle of least privilege should be applied by configuring TFTP servers with minimal necessary permissions and restricting their access to specific directories. Network monitoring should be enhanced to detect unusual TFTP traffic patterns, particularly those containing directory traversal sequences. Additionally, administrators should consider implementing firewall rules that restrict TFTP server access to trusted network segments only, and conduct regular security assessments to identify any other potential vulnerabilities in the network infrastructure. This vulnerability aligns with ATT&CK technique T1211 which involves the use of directory traversal to access restricted files, and T1078 which covers legitimate credentials use for persistence and privilege escalation.