CVE-2006-5526 in Fully Modded phpBB
Summary
by MITRE
Multiple PHP remote file inclusion vulnerabilities in Teake Nutma Foing, as modified in Fully Modded phpBB (phpbbfm) 2021.4.40 and earlier, allow remote attackers to execute arbitrary PHP code via a URL in the foing_root_path parameter in (a) faq.php, (b) index.php, (c) list.php, (d) login.php, (e) playlist.php, (f) song.php, (g) gen_m3u.php, (h) view_artist.php, (i) view_song.php, (j) flash/set_na.php, (k) flash/initialise.php, (l) flash/get_song.php, (m) includes/common.php, (n) admin/nav.php, (o) admin/main.php, (p) admin/list_artists.php, (q) admin/index.php, (r) admin/genres.php, (s) admin/edit_artist.php, (t) admin/edit_album.php, (u) admin/config.php, and (v) admin/admin_status.php in player/, different vectors than CVE-2006-3045. NOTE: CVE analysis as of 20061026 indicates that files in the admin/ and flash/ directories define foing_root_path before use.
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Analysis
by VulDB Data Team • 04/25/2026
This vulnerability represents a critical remote file inclusion flaw in the Fully Modded phpBB (phpbbfm) 2021.4.40 and earlier versions of the Teake Nutma Foing application. The issue stems from improper input validation where the foing_root_path parameter is directly incorporated into file inclusion operations without adequate sanitization. Attackers can exploit this weakness by supplying malicious URLs through the vulnerable parameters, enabling arbitrary PHP code execution on the target server. The vulnerability affects a comprehensive list of files across multiple directories including player/, admin/, and flash/ components, making it particularly dangerous as it spans across different application functionalities and administrative interfaces.
The technical implementation of this vulnerability aligns with common CWE categories including CWE-88 (Argument Injection in Canonical Form) and CWE-94 (Improper Control of Generation of Code) which classify it as a code injection vulnerability. The flaw occurs when user-supplied input is concatenated directly into file inclusion statements, creating an environment where remote attackers can load and execute arbitrary PHP scripts from external servers. This type of vulnerability is particularly concerning because it allows for complete system compromise, enabling attackers to establish persistent backdoors, exfiltrate sensitive data, or perform further lateral movement within the compromised network infrastructure.
The operational impact of this vulnerability is severe and multifaceted, as it affects core application functionality across multiple user and administrative interfaces. Attackers can leverage this vulnerability to gain unauthorized access to the server, potentially compromising the entire phpBB forum installation and underlying system resources. The wide scope of affected files means that an attacker could target different attack vectors depending on their objectives, from simple code execution in public-facing pages to more sophisticated attacks through administrative interfaces that provide deeper system access. This vulnerability essentially provides a gateway for attackers to escalate privileges and maintain persistent access to the compromised environment.
Security mitigations for this vulnerability should focus on input validation and sanitization at multiple levels. The most effective immediate solution involves implementing strict parameter validation to ensure that only trusted paths are accepted for file inclusion operations. Organizations should also consider implementing web application firewalls to detect and block suspicious file inclusion patterns, while applying the latest security patches from the vendor when available. Additionally, the principle of least privilege should be enforced by restricting file inclusion capabilities to only necessary components and ensuring that all user inputs are properly escaped before being processed by the application. This vulnerability demonstrates the critical importance of secure coding practices and proper input validation in preventing remote code execution attacks that can lead to complete system compromise. The ATT&CK framework categorizes this as a code injection technique under T1059.007 (Python) with potential lateral movement capabilities through T1078.004 (Valid Accounts) and privilege escalation through T1548.001 (Abuse Elevation Control Mechanism), making it a significant concern for enterprise security posture.