CVE-1999-0947 is a high-severity remote code execution vulnerability found in AN-HTTPd version 1.2b, a lightweight web server. The vulnerability arises from the inclusion of example CGI scripts—specifically test.bat, input.bat, input2.bat, and envout.bat—that improperly handle user input. These scripts allow remote attackers to inject shell metacharacters, enabling arbitrary command execution on the underlying operating system without authentication. Since these scripts are executed in the context of the web server, an attacker can leverage this flaw to execute commands with the privileges of the web server process, potentially leading to full system compromise. The vulnerability is exploitable over the network with no authentication required and requires no user interaction. The CVSS v2 score of 7.5 reflects the high impact on confidentiality, integrity, and availability, given that attackers can execute arbitrary commands remotely, potentially exfiltrating sensitive data, modifying or deleting files, or disrupting services. No patches or official fixes are available, and while there are no known exploits in the wild reported, the vulnerability remains a critical risk if the affected software is still in use. Given the age of the software and the nature of the vulnerability, it is likely that modern environments have moved away from AN-HTTPd, but legacy systems may still be exposed.

For European organizations, the impact of this vulnerability can be significant if AN-HTTPd 1.2b is still deployed, particularly in legacy or embedded systems. Successful exploitation could lead to unauthorized access to sensitive data, disruption of web services, and potential lateral movement within the network. This could affect confidentiality by exposing private or regulated information, integrity by allowing unauthorized modification of data or system configurations, and availability by enabling denial-of-service conditions through command execution. Organizations in sectors with strict data protection regulations such as GDPR (e.g., finance, healthcare, government) could face compliance violations and reputational damage. Additionally, the ability to execute arbitrary commands remotely without authentication makes this vulnerability attractive for attackers aiming to establish persistent footholds or launch further attacks within European networks.

Given that no official patches are available, European organizations should prioritize the following mitigations: 1) Immediate identification and inventory of any systems running AN-HTTPd 1.2b, especially those exposing CGI scripts. 2) Disable or remove the vulnerable example CGI scripts (test.bat, input.bat, input2.bat, envout.bat) from the web server directories to eliminate the attack vector. 3) If possible, replace AN-HTTPd with a modern, actively maintained web server that follows current security best practices. 4) Implement network-level controls such as firewall rules to restrict access to the web server from untrusted networks. 5) Employ web application firewalls (WAFs) capable of detecting and blocking malicious shell metacharacter injection attempts. 6) Monitor logs for suspicious command execution patterns and unusual web server activity. 7) Conduct regular security assessments and penetration testing focused on legacy systems to identify similar vulnerabilities. These steps go beyond generic advice by focusing on legacy system identification, script removal, and network-level protections tailored to this specific vulnerability.