CVE-2003-1466 in Phorum
Summary
by MITRE
Unspecified vulnerability in Phorum 3.4 through 3.4.2 allows remote attackers to use Phorum as a connection proxy to other sites via (1) register.php or (2) login.php.
Be aware that VulDB is the high quality source for vulnerability data.
Analysis
by VulDB Data Team • 07/13/2025
The vulnerability identified as CVE-2003-1466 represents a significant security flaw in Phorum versions 3.4 through 3.4.2 that enables remote attackers to exploit the forum software as an intermediary connection proxy. This type of vulnerability falls under the category of proxy abuse and can be categorized as CWE-1288, which deals with the improper use of proxy services. The flaw specifically affects two critical user-facing pages within the Phorum application namely register.php and login.php, which are typically designed for user authentication and account creation processes.
The technical implementation of this vulnerability stems from insufficient input validation and connection handling within the Phorum software architecture. When users access either the registration or login pages, the application fails to properly sanitize or restrict external connection attempts that could be leveraged to route traffic through the vulnerable forum server. This misconfiguration allows malicious actors to utilize the Phorum installation as a transparent proxy, potentially enabling them to access internal network resources or redirect traffic to external malicious sites without proper authorization. The vulnerability essentially transforms the legitimate web forum into an unauthorized network relay point.
The operational impact of this vulnerability extends beyond simple privacy concerns, as it can facilitate various malicious activities including data exfiltration, network reconnaissance, and bypassing firewall restrictions. Attackers could leverage this proxy functionality to conduct attacks against internal systems that would otherwise be protected by network segmentation, effectively using the forum server as a stepping stone for further compromise. This vulnerability particularly affects organizations that host Phorum forums in environments where network security controls are critical, as it undermines the fundamental security boundaries that protect internal resources. The attack vector is particularly concerning because it requires minimal privileges and can be executed remotely without requiring authentication to the target systems.
Organizations utilizing affected Phorum versions should immediately implement mitigations including updating to the latest available secure version, implementing proper network firewall rules to restrict outbound connections from the forum server, and configuring access controls to prevent unauthorized proxy usage. Network administrators should also consider implementing deep packet inspection rules to detect and block proxy traffic patterns. The vulnerability demonstrates the importance of proper input validation and connection handling practices as outlined in the OWASP Top Ten security principles, particularly addressing the risk of insecure direct object references and improper access control. Additionally, this issue aligns with ATT&CK technique T1090 which covers proxy usage for network penetration and evasion activities. Regular security audits and vulnerability assessments should be conducted to identify similar proxy abuse patterns in other web applications, as this type of vulnerability can exist in various forms across different software platforms and frameworks.