CVE-2000-0623 in Website Professional
Summary
by MITRE
Buffer overflow in O Reilly WebSite Professional web server 2.4 and earlier allows remote attackers to execute arbitrary commands via a long GET request or Referrer header.
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Analysis
by VulDB Data Team • 10/13/2025
The vulnerability identified as CVE-2000-0623 represents a critical buffer overflow flaw within the O Reilly WebSite Professional web server version 2.4 and earlier implementations. This security weakness stems from inadequate input validation mechanisms that fail to properly handle excessively long string data within HTTP request parameters. The flaw specifically manifests when the web server processes GET requests or Referrer headers that exceed predetermined buffer limits, creating exploitable conditions that can be leveraged by remote attackers to gain unauthorized system access.
The technical nature of this vulnerability aligns with CWE-121, which categorizes buffer overflow conditions where insufficient space is allocated for data storage, allowing attackers to overwrite adjacent memory locations. The flaw operates by placing maliciously crafted input data into the web server's memory buffers, specifically targeting the handling of HTTP headers and request parameters. When the server processes these oversized inputs without proper bounds checking, the excess data overflows into adjacent memory segments, potentially corrupting critical program execution structures or injecting malicious code sequences.
From an operational perspective, this vulnerability presents a severe threat to web server security as it enables remote code execution capabilities without requiring authentication or privileged access. Attackers can exploit this weakness by crafting specially formatted HTTP GET requests or manipulating Referrer headers to trigger the buffer overflow condition. The implications extend beyond simple service disruption, as successful exploitation can lead to complete system compromise, unauthorized data access, and potential lateral movement within network environments. This vulnerability directly maps to ATT&CK technique T1190, which describes the exploitation of vulnerabilities in web applications to execute arbitrary code remotely.
The mitigation strategies for CVE-2000-0623 involve immediate patching of affected web server installations to version 2.5 or later, which includes proper input validation and buffer management controls. Organizations should implement network segmentation and access controls to limit exposure, while also deploying intrusion detection systems capable of identifying suspicious HTTP request patterns. Additionally, regular security assessments and input validation reviews should be conducted to prevent similar vulnerabilities in custom web applications. The remediation process must also include comprehensive testing of patched systems to ensure that the buffer overflow protections function correctly without introducing new operational issues. Security teams should monitor for exploitation attempts and maintain updated threat intelligence regarding similar buffer overflow vulnerabilities that may affect other web server implementations.