CVE-2000-0766 in vqServer
Summary
by MITRE
Buffer overflow in vqSoft vqServer 1.4.49 allows remote attackers to cause a denial of service or possibly gain privileges via a long HTTP GET request.
Be aware that VulDB is the high quality source for vulnerability data.
Analysis
by VulDB Data Team • 12/23/2024
The vulnerability identified as CVE-2000-0766 represents a critical buffer overflow flaw within vqSoft vqServer version 1.4.49, a web server application that was widely deployed in enterprise environments during the late 1990s and early 2000s. This particular vulnerability resides in the handling of HTTP GET requests, specifically when processing overly long parameter strings that exceed the allocated buffer space within the server's memory management system. The flaw manifests when the application fails to properly validate the length of incoming HTTP GET parameters, allowing malicious actors to craft specially crafted requests that deliberately exceed buffer boundaries. The vulnerability is classified under CWE-121 as a stack-based buffer overflow, which occurs when more data is written to a fixed-length buffer than it can accommodate, leading to memory corruption and potential arbitrary code execution.
The operational impact of this vulnerability extends beyond simple denial of service conditions to potentially enable privilege escalation attacks that could allow remote attackers to gain elevated system privileges. When an attacker sends a long HTTP GET request containing excessive data, the buffer overflow can overwrite adjacent memory locations including return addresses, function pointers, or other critical control structures within the application's execution context. This memory corruption can cause the web server process to crash and restart, resulting in a denial of service that disrupts legitimate user access to web applications hosted on the affected server. However, the more severe implications arise when the overflow allows attackers to manipulate the program's execution flow, potentially enabling them to inject and execute malicious code within the server's memory space, thereby achieving unauthorized access to the underlying system.
The attack vector for CVE-2000-0766 operates through standard HTTP communication protocols, making it particularly dangerous as it requires no specialized tools or privileged access to exploit. Attackers can leverage automated scanning tools to identify vulnerable vqServer installations and then craft HTTP GET requests with carefully constructed payloads that exceed buffer limits by hundreds or thousands of bytes. The vulnerability's exploitation aligns with ATT&CK technique T1203 - Exploitation for Client Execution, as it targets the web server application directly through network-based attacks. Given that vqServer was commonly used to host web applications and services, successful exploitation could compromise entire web infrastructures, potentially leading to complete system takeover. The lack of input validation in the HTTP GET parameter handling mechanism creates an inherent weakness that attackers can exploit without needing to understand the underlying server architecture or implementation details.
Mitigation strategies for this vulnerability require immediate patching of affected vqServer installations to version 1.4.50 or later, which contains the necessary buffer overflow protections and input validation mechanisms. Network administrators should implement firewall rules to limit access to the web server and monitor for suspicious HTTP GET requests that exceed normal parameter lengths, though this approach provides only partial protection. Additional security measures include implementing application-level firewalls or web application firewalls that can detect and block malformed HTTP requests before they reach the vulnerable server components. The vulnerability highlights the importance of proper buffer management and input validation practices, which are fundamental requirements in secure software development and align with industry standards such as the OWASP Top Ten and NIST cybersecurity guidelines. Organizations should also conduct regular vulnerability assessments and penetration testing to identify similar buffer overflow vulnerabilities in other web server applications and ensure comprehensive patch management processes are in place to address such critical security flaws promptly.