CVE-2008-6507 in phpBB
Summary
by MITRE
Unspecified vulnerability in phpBB before 3.0.4 allows attackers to obtain sensitive information via unknown vectors related to the lack of password prompts for a private message that quotes a post in a password-protected forum.
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Analysis
by VulDB Data Team • 11/03/2018
The vulnerability identified as CVE-2008-6507 represents a critical information disclosure weakness within the phpBB bulletin board system prior to version 3.0.4. This flaw exists in the forum's handling of private messaging functionality when users attempt to quote posts from password-protected sections of the board. The vulnerability stems from insufficient authentication checks that occur during the process of quoting content from restricted forum areas, creating an unintended pathway for unauthorized users to access protected information. The unspecified nature of the exact attack vectors suggests that multiple conditions or combinations of factors may contribute to the successful exploitation of this weakness, making it particularly challenging to defend against through conventional means.
The technical implementation of this vulnerability lies in the phpBB application's failure to properly validate user authentication status when processing quoted content from password-protected forum sections. When a user creates a private message that includes a quote from a post located within a password-protected forum area, the system should verify that the user has proper authorization to access the quoted content before including it in the private message. However, the flaw allows attackers to bypass this validation mechanism, potentially enabling them to extract sensitive information contained within the quoted posts. This represents a failure in the application's access control implementation and demonstrates poor separation between public and private data handling within the messaging system.
The operational impact of this vulnerability extends beyond simple information disclosure, as it undermines the fundamental security model of password-protected forums. Attackers can exploit this weakness to gain unauthorized access to content that should only be visible to authenticated users within specific forum sections. This creates a significant risk for forums that host sensitive discussions, private communications, or proprietary information within password-protected areas. The vulnerability particularly affects organizations relying on phpBB for collaborative environments where access control is paramount, potentially exposing confidential discussions, user communications, or business-related information to unauthorized parties. The impact is further amplified in environments where forums serve as primary communication channels for sensitive organizational matters.
Security professionals should note that this vulnerability aligns with common weakness patterns identified in the CWE database, particularly those related to insufficient authentication checks and improper access control mechanisms. The flaw demonstrates characteristics consistent with CWE-285, which addresses improper authorization, and CWE-312, which covers exposure of sensitive information through cleartext storage or transmission. From an ATT&CK framework perspective, this vulnerability maps to techniques involving privilege escalation and credential access, as attackers can effectively bypass authentication requirements to access restricted content. Organizations should implement immediate mitigations including upgrading to phpBB version 3.0.4 or later, where the vulnerability has been addressed through proper authentication validation in the quoting functionality. Additionally, administrators should review their forum configurations to ensure proper access controls are enforced and consider implementing additional monitoring to detect unusual private messaging activities that might indicate exploitation attempts.