CVE-2000-1101 in WFTPD
Summary
by MITRE
Directory traversal vulnerability in Winsock FTPd (WFTPD) 3.00 and 2.41 with the "Restrict to home directory" option enabled allows local users to escape the home directory via a "/../" string, a variation of the .. (dot dot) attack.
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Analysis
by VulDB Data Team • 05/18/2019
The vulnerability described in CVE-2000-1101 represents a critical directory traversal flaw within the Winsock FTPd (WFTPD) software versions 2.41 and 3.00. This security weakness specifically manifests when the "Restrict to home directory" feature is enabled, creating a pathway for local attackers to bypass intended directory restrictions. The flaw exploits the improper handling of directory navigation sequences, allowing malicious users to traverse beyond their designated home directories through the use of the "/../" string pattern. This type of vulnerability falls under the category of path traversal attacks that have been consistently identified as high-risk security issues in network services.
The technical implementation of this vulnerability stems from inadequate input validation and path resolution mechanisms within the FTP server software. When the Restrict to home directory option is active, the system should normally prevent users from accessing files outside their designated directories. However, the flawed implementation fails to properly sanitize or process directory traversal sequences such as "../" or "/../" that are commonly used in Unix-like systems to navigate up directory levels. The attack vector specifically leverages the fact that the software does not adequately normalize or validate path components before processing user requests, allowing an attacker to construct malicious file paths that circumvent the intended directory restrictions.
From an operational standpoint, this vulnerability presents significant risks to organizations relying on WFTPD for file transfer services. Local users who can exploit this flaw gain the ability to access files and directories outside their home directories, potentially exposing sensitive data, system configuration files, or other restricted resources. The impact extends beyond simple information disclosure as attackers may be able to read system files, access other user directories, or potentially execute unauthorized operations depending on the permissions and access controls in place. This vulnerability particularly affects environments where multiple users share the same system and rely on directory restrictions for security isolation.
The security implications of this vulnerability align with CWE-22, which describes improper limitation of a pathname to a restricted directory, commonly known as path traversal or directory traversal. This weakness is classified as a fundamental flaw in input validation that has been consistently exploited across various platforms and applications. The attack pattern utilized in CVE-2000-1101 corresponds to the technique documented in the MITRE ATT&CK framework under the T1083 technique for discovering files and directories, where adversaries attempt to enumerate system resources through path manipulation. Organizations should consider implementing robust input validation measures, including proper path normalization and canonicalization, to prevent such attacks from succeeding. The vulnerability also highlights the importance of proper access control implementation and the necessity of regularly updating and patching network services to address known security flaws. Mitigation strategies should include immediate patch application, implementation of additional access controls, and monitoring for unauthorized access attempts that may indicate exploitation of this vulnerability.