CVE-2000-0150 is a high-severity vulnerability affecting multiple versions of Check Point's Firewall-1 product, specifically versions 3.0 through 5.0. The vulnerability arises from the firewall's improper handling of FTP passive mode (PASV) responses. In FTP passive mode, the client requests the server to open a port for data transfer, and the server responds with a 227 response containing the IP address and port number to connect to. Due to a flaw in Firewall-1's parsing logic, an attacker can craft malicious packets that the firewall misinterprets as valid 227 responses. This misinterpretation allows remote attackers to bypass the firewall's port access restrictions, effectively circumventing the intended security controls on FTP traffic. The vulnerability does not require authentication and can be exploited remotely over the network with low complexity, making it a significant risk. The CVSS score of 7.5 reflects the potential for confidentiality, integrity, and availability impacts, as attackers could gain unauthorized access to internal FTP servers or exfiltrate data by bypassing firewall rules. Notably, no patches are available for this vulnerability, which increases the risk for organizations still running affected versions. Although no known exploits are reported in the wild, the nature of the vulnerability and the widespread historical use of Check Point Firewall-1 in enterprise environments make it a critical concern for legacy systems still in operation.

For European organizations, the impact of CVE-2000-0150 can be substantial, especially for those relying on legacy Check Point Firewall-1 deployments to protect FTP servers. Successful exploitation could lead to unauthorized access to sensitive data transferred via FTP, data exfiltration, or lateral movement within the network. This undermines the confidentiality and integrity of data and may disrupt availability if attackers manipulate FTP sessions or flood internal resources. Sectors such as finance, manufacturing, and government agencies that historically used Check Point products and still maintain legacy infrastructure are at higher risk. Additionally, organizations subject to strict data protection regulations like GDPR could face compliance violations and reputational damage if breaches occur due to this vulnerability. The lack of patches means that mitigation relies heavily on compensating controls, increasing operational complexity and risk exposure.

Given the absence of official patches, European organizations should implement specific mitigations beyond generic advice: 1) Disable or restrict FTP passive mode usage where possible, or replace FTP with more secure protocols such as SFTP or FTPS to avoid reliance on vulnerable FTP parsing. 2) Deploy network segmentation to isolate FTP servers behind additional layers of security, limiting exposure if firewall bypass occurs. 3) Implement strict egress and ingress filtering rules on perimeter devices to monitor and block anomalous FTP traffic patterns indicative of exploitation attempts. 4) Use intrusion detection/prevention systems (IDS/IPS) with signatures or heuristics targeting malformed FTP 227 responses or suspicious PASV commands. 5) Conduct thorough network traffic analysis and logging focused on FTP sessions to detect unusual connection attempts or data flows. 6) Plan and execute an upgrade or migration away from legacy Check Point Firewall-1 versions to supported, patched firewall solutions. 7) Educate network and security teams about this specific vulnerability to increase awareness and readiness to respond to potential incidents.