CVE-2002-1003 in MyWebServer
Summary
by MITRE
Buffer overflow in MyWebServer 1.02 and earlier allows remote attackers to execute arbitrary code via a long HTTP GET request.
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Analysis
by VulDB Data Team • 09/10/2025
The vulnerability identified as CVE-2002-1003 represents a critical buffer overflow flaw in MyWebServer version 1.02 and earlier implementations. This security weakness resides in the server's handling of HTTP GET requests, where the application fails to properly validate input length before processing user-supplied data. The buffer overflow occurs when an attacker crafts an excessively long HTTP GET request that exceeds the allocated memory buffer size, causing adjacent memory to be overwritten with malicious data. This fundamental flaw in input validation creates a pathway for remote code execution, allowing attackers to inject and execute arbitrary commands on the vulnerable system. The vulnerability is particularly concerning as it operates entirely over the network without requiring any authentication or local access, making it highly exploitable in automated attack scenarios.
The technical implementation of this buffer overflow stems from inadequate bounds checking within the web server's request parsing routine. When processing HTTP GET requests, MyWebServer allocates a fixed-size buffer to store the request line, typically containing the method, URI, and protocol version. However, the application does not enforce maximum length constraints on the URI component, which directly translates to the vulnerable buffer. This weakness maps directly to CWE-121, which describes heap-based buffer overflow conditions where insufficient bounds checking allows attackers to overwrite adjacent memory locations. The overflow can overwrite return addresses, function pointers, or other critical control data structures, enabling attackers to redirect program execution flow. The attack vector operates entirely through standard HTTP traffic, making it difficult to detect through conventional network monitoring and allowing for stealthy exploitation.
The operational impact of CVE-2002-1003 extends beyond simple remote code execution to encompass complete system compromise and potential lateral movement within network environments. Once exploited, attackers can gain full control over the affected web server, potentially using it as a pivot point to access internal network resources or establish persistent backdoors. The vulnerability affects systems running MyWebServer 1.02 and earlier versions, which were widely deployed in enterprise and small business environments during the early 2000s. The consequences include data theft, service disruption, and potential establishment of command and control channels for further attacks. This vulnerability aligns with ATT&CK technique T1203, which covers exploitation for execution through buffer overflow attacks, and T1071.001, covering application layer protocol usage for command and control communications.
Mitigation strategies for CVE-2002-1003 require immediate action to address the root cause through proper input validation and application updates. Organizations should implement immediate network segmentation and access controls to limit exposure to this vulnerability, particularly in environments where MyWebServer instances remain operational. The most effective remediation involves upgrading to MyWebServer versions that properly implement input validation and buffer size checking for HTTP requests. Network administrators should also deploy intrusion detection systems that can identify and block unusually long HTTP GET requests that exceed typical application behavior. Additionally, implementing web application firewalls and HTTP request filtering can help prevent exploitation attempts by blocking malformed requests before they reach the vulnerable application. The vulnerability demonstrates the critical importance of input validation and proper memory management in web server implementations, aligning with security best practices outlined in OWASP Top Ten and NIST cybersecurity frameworks. Regular vulnerability assessments and security patch management programs are essential to prevent similar issues in modern web applications and infrastructure components.