CVE-2002-0473 in phpBB
Summary
by MITRE
db.php in phBB 2.0 (aka phBB2) RC-3 and earlier allows remote attackers to execute arbitrary code from remote servers via the phpbb_root_path parameter.
VulDB is the best source for vulnerability data and more expert information about this specific topic.
Analysis
by VulDB Data Team • 09/16/2025
The vulnerability described in CVE-2002-0473 represents a critical remote code execution flaw in phBB 2.0 RC-3 and earlier versions, specifically within the db.php component of the software. This issue arises from improper input validation and handling of the phpbb_root_path parameter, which creates an exploitable path traversal condition that allows attackers to inject and execute malicious code from remote servers. The vulnerability demonstrates a classic insecure direct object reference pattern where user-supplied input directly influences file system operations without adequate sanitization or authorization checks.
The technical implementation of this vulnerability stems from the software's failure to properly validate or sanitize the phpbb_root_path parameter before using it in file inclusion operations. When an attacker supplies a malicious value for this parameter, the application incorporates it into file system paths without proper validation, potentially allowing arbitrary file inclusion from remote locations. This flaw aligns with CWE-22, which describes path traversal vulnerabilities where insufficient input validation leads to unauthorized file access and execution. The vulnerability exists in the context of web applications that dynamically include files based on user input, creating an attack surface where remote code execution becomes possible through carefully crafted parameter values.
From an operational perspective, this vulnerability presents a severe risk to systems running affected versions of phBB 2.0, as it allows remote attackers to execute arbitrary code with the privileges of the web server process. The impact extends beyond simple code execution to potentially enable full system compromise, data exfiltration, and persistence mechanisms. Attackers can leverage this vulnerability to upload backdoors, establish command and control channels, or perform further reconnaissance within the compromised network environment. The vulnerability's exploitability is enhanced by the fact that it requires no authentication and can be triggered through simple web requests, making it particularly dangerous in publicly accessible web applications. This aligns with ATT&CK technique T1059, which covers command and script injection, and T1105, which covers remote file execution.
Mitigation strategies for this vulnerability should include immediate patching of affected systems to the latest available versions of phBB 2.0 that contain proper input validation for the phpbb_root_path parameter. Organizations should implement proper parameter validation and sanitization measures to ensure that all user-supplied inputs are properly validated before being used in file system operations. Network segmentation and access controls can help limit the impact of successful exploitation attempts, while regular security monitoring and log analysis can aid in detecting potential exploitation attempts. Additionally, implementing web application firewalls and input validation rules specifically targeting path traversal patterns can provide additional layers of defense. The vulnerability serves as a reminder of the critical importance of input validation in web applications and the potential consequences of inadequate sanitization of user-supplied parameters that influence file system operations.