CVE-1999-0487 is a security vulnerability affecting the DHTML Edit ActiveX control in Microsoft Internet Explorer versions 4.0 and 5.0. This vulnerability allows remote attackers to read arbitrary files on the victim's system by exploiting the ActiveX control's improper handling of file access permissions. Specifically, the flaw enables attackers to bypass intended security restrictions and access files that should be protected, potentially exposing sensitive information. The vulnerability is classified as a remote, network-based attack vector with no authentication required, but it has a high attack complexity, meaning exploitation is not straightforward. The impact is limited to confidentiality, as attackers can read files but cannot modify them or disrupt system availability. Microsoft addressed this vulnerability with a security bulletin (MS99-011) that provides patches to fix the issue. Given the age of the vulnerability and the affected product versions, modern systems are unlikely to be impacted; however, legacy systems or environments still running these outdated Internet Explorer versions remain at risk. No known exploits have been reported in the wild, which further reduces the immediate threat level. The vulnerability's CVSS score is 2.6 (low severity), reflecting limited impact and exploitation difficulty.

For European organizations, the impact of this vulnerability is generally low due to the obsolescence of the affected Internet Explorer versions (4.0 and 5.0). However, organizations that maintain legacy systems or specialized industrial environments where these versions are still in use could face confidentiality risks. Attackers exploiting this vulnerability could gain unauthorized read access to sensitive files, potentially exposing intellectual property, personal data, or configuration files. This could lead to information leakage and subsequent targeted attacks. The vulnerability does not allow modification or disruption, so integrity and availability impacts are minimal. Given the low CVSS score and absence of known exploits, the immediate risk to European organizations is limited but should not be ignored in legacy contexts.

European organizations should ensure that all systems are updated to supported versions of web browsers and operating systems, eliminating the use of Internet Explorer 4.0 and 5.0. For legacy systems where upgrading is not feasible, organizations should apply the official Microsoft patch MS99-011 to remediate the vulnerability. Additionally, organizations should implement network-level controls to restrict access to legacy systems, such as firewall rules limiting inbound connections and segmentation to isolate vulnerable hosts. Employing application whitelisting and disabling or restricting ActiveX controls in Internet Explorer can further reduce attack surface. Regular audits to identify and inventory legacy software use are critical. Finally, user education about the risks of using outdated browsers and the importance of patching should be reinforced.