CVE-2000-0114 is a medium severity vulnerability affecting Microsoft Internet Information Server (IIS) versions 3.0 and 4.0, specifically related to the FrontPage Server Extensions component. The vulnerability allows remote attackers to determine the name of the anonymous account configured on the server by sending a crafted RPC POST request to the shtml.dll file located in the /_vti_bin/ virtual directory. This directory is part of the FrontPage Server Extensions, which enable web authors to publish and manage content on IIS servers. By exploiting this vulnerability, an attacker can enumerate the anonymous user account name without requiring authentication or user interaction. The vulnerability has a CVSS base score of 5.0, indicating a medium severity level, with an attack vector that is network-based, low attack complexity, no authentication required, and impacts confidentiality by disclosing sensitive configuration information. There is no patch available for this vulnerability, and no known exploits have been reported in the wild. Although the vulnerability does not allow direct compromise of system integrity or availability, knowledge of the anonymous account name can aid attackers in crafting further attacks or privilege escalation attempts against the affected IIS servers.

For European organizations running legacy IIS 3.0 or 4.0 servers with FrontPage Server Extensions enabled, this vulnerability poses a risk of information disclosure. Knowing the anonymous account name can facilitate targeted attacks such as unauthorized access attempts, privilege escalation, or exploitation of other vulnerabilities that rely on this information. While the direct impact is limited to confidentiality, the disclosed information can be a stepping stone in a broader attack chain, especially in environments where legacy systems are still in use or where defense-in-depth controls are weak. Given that these IIS versions are outdated and generally unsupported, organizations may face challenges in mitigating risks if they continue to operate such systems. European organizations in sectors with legacy web infrastructure, such as government, manufacturing, or utilities, may be particularly vulnerable if they have not upgraded or isolated these servers. The vulnerability does not directly impact availability or integrity but can contribute to more severe attacks if combined with other vulnerabilities or misconfigurations.

Since no official patch is available for CVE-2000-0114, European organizations should prioritize the following specific mitigation steps: 1) Upgrade IIS servers to supported versions that do not include the vulnerable FrontPage Server Extensions or have this vulnerability addressed. 2) If upgrading is not immediately feasible, disable or remove FrontPage Server Extensions entirely to eliminate the attack surface. 3) Restrict access to the /_vti_bin/ virtual directory using network-level controls such as firewalls or IIS IP restrictions to limit exposure to trusted hosts only. 4) Implement strict monitoring and logging of requests to the /_vti_bin/shtml.dll endpoint to detect suspicious RPC POST requests indicative of reconnaissance attempts. 5) Conduct regular security assessments and audits to identify legacy systems and ensure they are either upgraded, isolated, or decommissioned. 6) Employ web application firewalls (WAFs) with custom rules to block or alert on anomalous requests targeting FrontPage Server Extensions endpoints. 7) Educate IT staff about the risks of legacy components and the importance of timely patching and system upgrades.