CVE-2000-0067 is a vulnerability identified in the CyberCash Merchant Connection Kit (MCK) version 3.2.0.4. This vulnerability allows local users to perform a symlink (symbolic link) attack to modify files improperly. Specifically, the flaw arises because the software does not securely handle file operations, allowing an attacker with local access to create symbolic links that redirect file writes or modifications to arbitrary files elsewhere in the filesystem. This can lead to unauthorized modification of files that the attacker should not have permission to alter. The vulnerability requires local access, meaning the attacker must already have some level of access to the system where MCK is installed. The CVSS v2 score is 2.1, indicating a low severity primarily due to the requirement of local access and the limited impact scope. The vulnerability impacts confidentiality partially, as unauthorized file modifications could expose or alter sensitive data, but it does not affect integrity or availability directly. No patches or fixes are available for this vulnerability, and there are no known exploits in the wild. Given the age of the vulnerability (published in 2000), it is likely that this software version is outdated and possibly no longer in active use or supported.

For European organizations, the impact of this vulnerability is generally low due to several factors. First, the vulnerability requires local access, which limits the attack surface to insiders or users who have already compromised the system. Second, the affected product, CyberCash Merchant Connection Kit version 3.2.0.4, is an older payment processing component that may not be widely deployed in modern environments. However, if legacy systems still use this software, unauthorized file modifications could lead to exposure or alteration of sensitive payment or transaction data, potentially causing compliance issues with GDPR and financial regulations. The risk is higher in organizations with weak internal access controls or where legacy payment systems are still operational. The vulnerability does not directly impact system availability or integrity on a broad scale, but targeted file modifications could disrupt specific processes or data confidentiality.

Given that no official patches are available, European organizations should take the following practical steps: 1) Identify and inventory any systems running CyberCash Merchant Connection Kit version 3.2.0.4 or similar legacy payment software. 2) Restrict local access strictly to trusted and authorized personnel only, employing the principle of least privilege to minimize the risk of local exploitation. 3) Implement file system monitoring and integrity checking tools to detect unauthorized file modifications, especially in directories used by the MCK software. 4) Consider isolating legacy payment systems in segmented network zones with strict access controls to reduce insider threat risks. 5) Where possible, upgrade or replace the legacy CyberCash MCK software with modern, supported payment processing solutions that have active security maintenance. 6) Conduct regular security audits and user activity logging to detect suspicious local user behavior that could exploit this vulnerability.