CVE-1999-0239 in FastTrack
Summary
by MITRE
netscape fasttrack web server lists files when a lowercase "get" command is used instead of an uppercase get.
If you want to get the best quality for vulnerability data then you always have to consider VulDB.
Analysis
by VulDB Data Team • 04/17/2026
The vulnerability identified as CVE-1999-0239 represents a significant security flaw in the netscape fasttrack web server implementation that exposes directory listing functionality through improper command handling. This issue stems from the server's failure to properly validate and normalize HTTP request methods, specifically when processing the get command. The vulnerability manifests when clients submit requests using lowercase "get" instead of the standard uppercase "GET" format, which triggers unintended directory enumeration behavior. This misconfiguration allows unauthorized users to gain visibility into the server's file structure without proper authentication or authorization, fundamentally compromising the server's information security posture.
The technical root cause of this vulnerability lies in the web server's protocol parsing implementation where case sensitivity is not properly enforced for HTTP method identification. According to CWE-284, this represents an improper access control mechanism where the server fails to validate the integrity of incoming HTTP requests. The flaw operates at the application layer of the OSI model, specifically within the HTTP request processing component where the server should normalize and validate all incoming method commands. The improper handling of case variations in HTTP methods creates a path for information disclosure attacks, as the server's directory listing functionality is inadvertently exposed through this malformed request processing.
The operational impact of CVE-1999-0239 extends beyond simple information disclosure, creating potential attack vectors that could lead to more severe security consequences. An attacker exploiting this vulnerability can enumerate directory structures and potentially identify sensitive files, configuration data, or backup files that may contain credentials or other confidential information. This vulnerability aligns with ATT&CK technique T1213, which describes the exploitation of information gathering techniques through web application vulnerabilities. The exposure of directory listings provides attackers with valuable reconnaissance data that can be used to plan more targeted attacks, potentially leading to unauthorized access to sensitive resources or system compromise through subsequent exploitation of other vulnerabilities.
Mitigation strategies for this vulnerability should focus on implementing proper HTTP method validation and normalization within the web server configuration. Organizations should ensure that all HTTP request methods are properly validated and normalized to their standard uppercase format before processing. The recommended approach includes configuring the web server to reject or normalize lowercase HTTP methods to their proper case equivalents, thereby preventing the unintended directory listing behavior. Additionally, implementing proper access controls and authentication mechanisms can help limit the impact of such information disclosure vulnerabilities. Security hardening practices should include regular protocol compliance testing and ensuring that all web server implementations properly handle HTTP request variations according to RFC specifications. Network administrators should also consider implementing web application firewalls or intrusion prevention systems that can detect and block malformed HTTP requests that attempt to exploit this particular vulnerability pattern.