CVE-2000-0458 is a vulnerability found in the MSWordView application component of the IMP (Internet Messaging Program) software, specifically in versions 2.0.9, 2.0.10, 2.0.11, 2.2_pre9, and 2.2_pre10. The issue arises because MSWordView creates temporary files in the /tmp directory with world-readable permissions. This means that any local user on the affected system can read these files, potentially exposing sensitive information such as email content or document data that the application processes. The vulnerability is a local information disclosure flaw, as it requires local access to the system and does not allow modification or disruption of data or services. The CVSS score of 2.1 (low severity) reflects that the impact is limited to confidentiality, with no impact on integrity or availability. Exploitation does not require authentication but does require local access, and no user interaction beyond running the vulnerable application is needed. No patches or fixes are available for this vulnerability, and there are no known exploits in the wild. The vulnerability is primarily a privacy risk in multi-user environments where untrusted users share the same system, such as shared servers or workstations.

For European organizations, the impact of this vulnerability is primarily related to confidentiality breaches in environments where multiple users have local access to the same system. Organizations using IMP versions affected by this vulnerability on shared servers or multi-user systems risk unauthorized disclosure of sensitive email or document content. This could lead to exposure of confidential business communications, personal data, or intellectual property. However, since exploitation requires local access and does not affect system integrity or availability, the overall risk is limited to insider threats or compromised local accounts. The lack of a patch means organizations must rely on mitigating controls. The vulnerability is less likely to impact organizations that use dedicated user environments or have strict local access controls. Given the age of the vulnerability (published in 2000), modern deployments are less likely to be affected, but legacy systems in use within some European organizations could still be vulnerable.

To mitigate this vulnerability, European organizations should: 1) Restrict local user access on systems running affected IMP versions to trusted personnel only, minimizing the risk of unauthorized local users reading temporary files. 2) Implement strict file system permissions and consider mounting /tmp with the 'noexec' and 'nosuid' options and using access control lists (ACLs) to limit read permissions on temporary files. 3) Use containerization or sandboxing techniques to isolate the IMP application and its temporary files from other users on the system. 4) Where possible, upgrade or replace IMP with more modern, supported mail clients that do not exhibit this vulnerability. 5) Monitor local system access logs for unusual activity that could indicate attempts to access temporary files. 6) If legacy systems must be maintained, consider relocating the /tmp directory to a location with stricter permissions or using tmpfs with controlled access. These steps go beyond generic advice by focusing on local access controls and file system hardening tailored to the nature of this vulnerability.