CVE-2001-0558 in Jana Web Server
Summary
by MITRE
T. Hauck Jana Webserver 2.01 beta 1 and earlier allows a remote attacker to create a denial of service via a URL request which includes a MS-DOS device name (i.e. GET /aux HTTP/1.0).
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Analysis
by VulDB Data Team • 10/05/2025
The vulnerability identified as CVE-2001-0558 affects T. Hauck Jana Webserver version 2.01 beta 1 and earlier implementations, representing a significant denial of service weakness that can be exploited remotely. This flaw stems from the web server's inadequate handling of specific URL requests containing MS-DOS device names, which are legacy identifiers from the windows operating system architecture. The vulnerability specifically manifests when the server processes a request formatted as GET /aux HTTP/1.0, where aux represents one of the reserved device names in MS-DOS file systems that include aux con nul com1 prn lpt1 through lpt9. These device names were originally designed to provide access to system hardware components and special devices within the MS-DOS environment, but they have no legitimate purpose in modern web server contexts.
The technical exploitation of this vulnerability occurs through the web server's improper parsing and handling of these reserved device names within URL paths. When the vulnerable web server receives a request containing such device names, it attempts to process them as if they were regular file paths, leading to system resource exhaustion or process termination. This behavior is rooted in the server's failure to implement proper input validation and sanitization mechanisms for URL components. The flaw operates at the application layer of the network stack and can be classified under CWE-20 as "Improper Input Validation," specifically manifesting as inadequate handling of special characters and reserved identifiers. The vulnerability represents a classic case of insufficient boundary checking and path traversal protection within web server implementations.
From an operational impact perspective, this vulnerability enables remote attackers to disrupt web server availability and cause denial of service conditions without requiring authentication or specialized access privileges. The attack can be executed through simple HTTP requests, making it particularly dangerous as it requires minimal effort to exploit and can be automated. The DoS condition can result in complete service unavailability, requiring manual intervention to restore normal operations, potentially leading to significant business disruption and loss of service availability for legitimate users. The vulnerability affects the core availability aspect of the web server's functionality, making it a critical concern for any organization relying on this particular web server implementation. According to ATT&CK framework, this vulnerability maps to T1499.004 - "Endpoint Denial of Service" within the Defense Evasion and Impact tactics, demonstrating how legacy system design flaws can create persistent security risks.
Mitigation strategies for this vulnerability should focus on immediate patching of the affected web server software to version 2.01 beta 2 or later, which contains the necessary fixes for proper URL path validation. Organizations should implement input validation measures that specifically filter or reject requests containing MS-DOS device names and other reserved identifiers. Network-level firewalls and web application firewalls can be configured to block requests containing these specific patterns, providing an additional layer of protection. System administrators should also consider implementing proper logging and monitoring to detect suspicious requests containing device names, which can help in identifying potential exploitation attempts. The vulnerability highlights the importance of maintaining up-to-date software versions and implementing comprehensive input validation across all application components. Security teams should conduct regular vulnerability assessments to identify similar legacy issues that may exist in other web server implementations and ensure proper security hardening practices are applied to prevent similar exploitation vectors.