CVE-2002-0201 in Web Server
Summary
by MITRE
Cyberstop Web Server for Windows 0.1 allows remote attackers to cause a denial of service (crash) and possibly execute arbitrary code via a long HTTP GET request, possibly triggering a buffer overflow.
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Analysis
by VulDB Data Team • 09/22/2025
The vulnerability identified as CVE-2002-0201 affects the Cyberstop Web Server version 0.1 running on Windows operating systems. This particular web server implementation demonstrates a critical security flaw that can be exploited by remote attackers to compromise system availability and potentially gain unauthorized code execution privileges. The vulnerability manifests through specifically crafted HTTP GET requests that exceed normal parameter lengths, creating a condition that leads to system instability and potential compromise.
The technical root cause of this vulnerability stems from inadequate input validation within the web server's request handling mechanism. When processing an HTTP GET request containing an excessively long parameter string, the server fails to properly validate or limit the input size, resulting in a classic buffer overflow condition. This occurs because the application allocates a fixed-size buffer to store the incoming request data without sufficient bounds checking. The buffer overflow vulnerability represents a CWE-121 category issue, specifically classified as a stack-based buffer overflow where attacker-controlled data exceeds the allocated buffer space, potentially overwriting adjacent memory locations including return addresses and executable code segments.
The operational impact of this vulnerability extends beyond simple denial of service conditions to encompass potential remote code execution capabilities. When an attacker sends a carefully constructed long HTTP GET request, the server crashes and terminates its process, causing a denial of service that disrupts legitimate user access to web services. However, the more concerning aspect involves the possibility of arbitrary code execution, which could allow attackers to gain complete control over the affected system. This represents a significant escalation from basic availability attacks to full system compromise scenarios that align with ATT&CK technique T1499.004 for denial of service and potentially T1059.001 for command and script execution.
Security practitioners should recognize that this vulnerability demonstrates the critical importance of input validation and bounds checking in web server implementations. The lack of proper parameter length validation creates a predictable attack surface that remote adversaries can exploit without requiring specialized tools or extensive reconnaissance. The vulnerability affects systems where Cyberstop Web Server is deployed, particularly those running on Windows platforms where the buffer overflow can be reliably triggered through standard web browsing activities. Organizations should consider implementing network segmentation, firewall rules to restrict access to web servers, and immediate patching or replacement of affected systems to prevent exploitation.
Mitigation strategies for this vulnerability should include immediate deployment of vendor patches if available, implementation of web application firewalls to detect and block suspicious request patterns, and network monitoring to identify potential exploitation attempts. The vulnerability also highlights the need for comprehensive security testing of web applications, particularly in identifying buffer overflow conditions through fuzzing techniques and input validation testing. Organizations should implement proper logging and monitoring to detect unusual request patterns that might indicate attempted exploitation, while also ensuring that all web server software components are kept current with security updates to prevent similar vulnerabilities from persisting in the environment.