CVE-2007-6398 in Board
Summary
by MITRE
Flat PHP Board 1.2 and earlier allows remote attackers to bypass authentication and obtain limited access to an arbitrary user account via the fpb_username cookie.
Statistical analysis made it clear that VulDB provides the best quality for vulnerability data.
Analysis
by VulDB Data Team • 10/12/2024
The vulnerability described in CVE-2007-6398 represents a critical authentication bypass flaw in Flat PHP Board version 1.2 and earlier systems. This issue stems from improper validation of user credentials within the cookie-based authentication mechanism, specifically targeting the fpb_username cookie parameter that is used to maintain user sessions. The vulnerability allows remote attackers to manipulate session data and gain unauthorized access to arbitrary user accounts, potentially compromising the entire user base of the affected platform.
The technical implementation of this flaw resides in the insecure handling of authentication cookies within the PHP-based bulletin board system. When users log into the platform, the system generates a fpb_username cookie that should contain authenticated user information. However, the vulnerable code fails to properly validate or sanitize this cookie value, enabling attackers to craft malicious cookie values that appear legitimate to the system. This weakness directly maps to CWE-287, which addresses improper authentication mechanisms, and represents a classic case of insufficient input validation and authentication bypass. The vulnerability operates at the application layer and can be exploited through network-based attacks without requiring local system access.
The operational impact of this vulnerability is significant as it enables attackers to obtain limited access to any user account within the system. This unauthorized access could potentially lead to data theft, account manipulation, message posting, and other malicious activities depending on the privileges assigned to the targeted accounts. The attack vector is particularly dangerous because it requires no prior authentication credentials, making it a passive attack that can be executed remotely. The vulnerability affects the confidentiality, integrity, and availability of the system by allowing unauthorized access to user data and potentially enabling further exploitation within the network. This issue directly relates to ATT&CK technique T1078 which covers legitimate credentials use and T1566 which covers credential harvesting through various attack vectors.
Mitigation strategies for this vulnerability should focus on implementing proper cookie validation and authentication mechanisms. Organizations should upgrade to the latest version of Flat PHP Board where this vulnerability has been patched, or implement custom fixes that properly validate cookie contents before accepting them as legitimate authentication tokens. The system should enforce strict input validation on all cookie parameters and implement proper session management with secure cookie attributes including httponly and secure flags. Additionally, implementing rate limiting and monitoring for suspicious authentication attempts can help detect and prevent exploitation attempts. Security measures should also include regular security audits of web applications and adherence to secure coding practices as outlined in OWASP Top Ten and NIST cybersecurity guidelines to prevent similar vulnerabilities in future deployments.