CVE-1999-0448 in IIS
Summary
by MITRE
IIS 4.0 and Apache log HTTP request methods, regardless of how long they are, allowing a remote attacker to hide the URL they really request.
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Analysis
by VulDB Data Team • 10/26/2025
This vulnerability exists in internet information services version 4.0 and apache web servers where the logging mechanism fails to properly truncate or validate http request methods. The flaw allows malicious actors to craft overly long http request methods that can bypass normal logging restrictions and potentially conceal the actual requested url. The vulnerability stems from inadequate input validation within the web server logging component that processes http requests. When a client sends a request with an extended method name, the server logs the complete method without proper sanitization, creating a potential information disclosure and obfuscation vector. This behavior violates standard security practices for input validation and can be exploited to hide malicious activities within web server logs. The issue is particularly concerning because it affects fundamental web server logging functionality that security teams rely upon for monitoring and forensic analysis. According to CWE standards, this represents a weakness in logging and error handling where insufficient input sanitization allows for data corruption or information disclosure. The vulnerability can be categorized under attack technique t1070 in the ATT&CK framework as it involves the use of log manipulation to obscure malicious activities.
The operational impact of this vulnerability extends beyond simple logging issues as it can enable attackers to evade detection mechanisms that depend on analyzing http request patterns. When combined with other techniques, attackers can craft requests that appear benign in logs while actually executing malicious operations. The extended method names can potentially cause buffer overflows or memory corruption in the logging components, especially when the web server processes extremely long method strings. Security monitoring systems that parse web server logs may misinterpret the truncated or malformed request data, leading to false negatives in intrusion detection. This vulnerability particularly affects environments where web server logs are used for security auditing, compliance monitoring, and incident response activities. The improper handling of http request methods creates a potential attack surface for information gathering and evasion techniques that can be exploited by advanced persistent threats. Organizations using affected web server versions may experience difficulties in forensic analysis due to corrupted or misleading log data that obscures actual attack patterns.
Mitigation strategies should focus on implementing strict input validation and length restrictions for http request methods within the web server configuration. Administrators should configure web servers to reject requests with excessively long method names or implement proper truncation mechanisms for logging purposes. The recommended approach involves setting maximum length limits for http method strings and ensuring that all http request processing components properly sanitize input data. Security patches should be applied to update web server implementations to properly handle extended method names without compromising functionality. Network security teams should enhance their monitoring systems to detect anomalous request patterns that may indicate exploitation attempts. Additional defensive measures include implementing web application firewalls that can filter out suspicious http method variations and establishing robust log integrity checking mechanisms. Organizations should also consider implementing intrusion detection systems that can identify malformed http requests and alert security personnel to potential exploitation attempts. The vulnerability highlights the importance of proper input validation in web server components and the need for regular security assessments of core infrastructure services. Regular security testing should include validation of http request handling mechanisms to prevent similar issues from occurring in other components of the web infrastructure stack.