CVE-2001-0205 in Server
Summary
by MITRE
Directory traversal vulnerability in AOLserver 3.2 and earlier allows remote attackers to read arbitrary files by inserting "..." into the requested pathname, a modified .. (dot dot) attack.
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Analysis
by VulDB Data Team • 02/28/2025
The vulnerability identified as CVE-2001-0205 represents a critical directory traversal flaw in AOLserver version 3.2 and earlier systems. This security weakness enables remote attackers to access files outside the intended directory structure by manipulating file path requests through the insertion of ".." sequences. The vulnerability fundamentally compromises the server's ability to properly validate and sanitize user-supplied input, creating an avenue for unauthorized data access. Such flaws typically arise from inadequate input validation mechanisms that fail to properly filter or escape special characters used in file path navigation. The attack vector specifically exploits the server's handling of dot-dot sequences that are commonly used in Unix-like operating systems to navigate up directory levels. This vulnerability falls under the CWE-22 category of Improper Limitation of a Pathname to a Restricted Directory, which is a well-documented weakness in software security architecture.
The technical implementation of this vulnerability allows attackers to bypass normal access controls by crafting malicious requests that include directory traversal sequences. When AOLserver processes these requests, it fails to properly sanitize the pathname input, enabling the server to interpret the ".." sequences as legitimate navigation commands rather than malicious input. This results in the server resolving file paths beyond the intended document root directory, potentially exposing sensitive system files, configuration data, or user information. The flaw demonstrates a classic lack of proper input validation and path normalization within the web server's file access routines. Attackers can leverage this vulnerability to retrieve system files such as password databases, configuration files, or application source code that should remain inaccessible to remote users. The impact is particularly severe because it can be exploited remotely without requiring authentication or special privileges, making it a highly attractive target for malicious actors seeking unauthorized system access.
The operational consequences of this vulnerability extend beyond simple information disclosure to potentially enable more sophisticated attacks within the compromised system. Once an attacker successfully exploits this vulnerability, they can access not only user files but also system configuration files that may contain database credentials, encryption keys, or other sensitive information. The vulnerability also creates opportunities for privilege escalation attacks where attackers might use the retrieved information to gain deeper access to the system. From an attacker's perspective, this vulnerability aligns with the MITRE ATT&CK framework's technique T1083 (File and Directory Discovery) and T1566 (Phishing with Malicious Attachments) when combined with other exploitation methods. The attack can be automated and requires minimal technical skill, making it a popular choice for both novice and experienced attackers. Organizations running affected versions of AOLserver face significant risk of data breaches, regulatory violations, and potential system compromise that could lead to extended downtime and financial losses.
Organizations should immediately implement mitigations that include updating to patched versions of AOLserver where available, as this vulnerability was addressed in later releases. System administrators should also implement proper input validation and sanitization measures that filter or reject any requests containing directory traversal sequences. Network-level protections such as web application firewalls can provide additional defense-in-depth by detecting and blocking malicious path traversal attempts. Regular security audits and vulnerability assessments should be conducted to identify similar weaknesses in other applications and systems. The implementation of proper access controls and least privilege principles can help limit the damage if exploitation occurs. Organizations should also establish incident response procedures specifically designed to handle directory traversal attacks and ensure that all system administrators are trained on recognizing and responding to such threats. Additionally, regular patch management processes should be implemented to ensure timely updates of all web server components and prevent similar vulnerabilities from remaining unaddressed in the organization's infrastructure.