CVE-1999-0669 is a vulnerability in the Eyedog ActiveX control used by Internet Explorer versions 4.0 and 5.0. The control is incorrectly marked as "safe for scripting," which means that Internet Explorer allows scripts on web pages to interact with the control without prompting the user for permission. This misclassification enables remote attackers to execute arbitrary commands on the victim's system by leveraging the control's scripting interface. The vulnerability was notably demonstrated by the Bubbleboy exploit, which used this flaw to run commands remotely without user consent. The vulnerability has a CVSS score of 4.0, indicating medium severity, with the vector indicating network attack vector, high attack complexity, no authentication required, partial confidentiality and integrity impact, and no availability impact. Since this vulnerability affects legacy versions of Internet Explorer that are no longer supported and no patches are available, systems still running these versions remain at risk if exposed to malicious web content that exploits this ActiveX control. The vulnerability primarily impacts the confidentiality and integrity of affected systems by allowing unauthorized command execution through scripting, potentially leading to data exposure or manipulation.

For European organizations, the impact of this vulnerability is largely historical but could still be relevant in legacy environments where Internet Explorer 4.0 or 5.0 is in use, particularly in industrial, governmental, or specialized systems that have not been updated. Exploitation could lead to unauthorized command execution, compromising sensitive data confidentiality and integrity. This could result in data breaches, unauthorized system changes, or further malware deployment. Although the vulnerability does not affect availability directly, the indirect consequences of compromised systems could disrupt business operations. Given the age of the vulnerability, modern browsers and systems are not affected; however, organizations with legacy dependencies could face significant risks if attackers target these outdated environments. The lack of available patches means mitigation relies on configuration and environment controls rather than software fixes.

1. Immediate mitigation involves disabling or restricting the use of ActiveX controls in Internet Explorer, especially the Eyedog control, through Group Policy or browser security settings. 2. Organizations should phase out the use of Internet Explorer versions 4.0 and 5.0, migrating to modern, supported browsers that do not rely on vulnerable ActiveX controls. 3. Implement network-level protections such as web filtering and intrusion detection systems to block or alert on attempts to exploit this vulnerability. 4. Use application whitelisting to prevent unauthorized execution of scripts or commands initiated via ActiveX controls. 5. Educate users about the risks of interacting with untrusted web content and disable scripting where possible in legacy systems. 6. For environments that must maintain legacy systems, isolate them from the internet and restrict access to trusted internal resources only. 7. Regularly audit and monitor legacy systems for signs of compromise or exploitation attempts related to this vulnerability.