CVE-2016-6174 in macOS
Summary
by MITRE
applications/core/modules/front/system/content.php in Invision Power Services IPS Community Suite (aka Invision Power Board, IPB, or Power Board) before 4.1.13, when used with PHP before 5.4.24 or 5.5.x before 5.5.8, allows remote attackers to execute arbitrary code via the content_class parameter.
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Analysis
by VulDB Data Team • 02/01/2025
The vulnerability CVE-2016-6174 represents a critical remote code execution flaw within the Invision Power Services IPS Community Suite, a widely deployed web forum platform that serves thousands of organizations globally. This vulnerability specifically affects the system's content handling mechanism, where the content_class parameter in the file applications/core/modules/front/system/content.php fails to properly validate user input. The flaw exists in versions prior to 4.1.13 and becomes exploitable when the platform operates with vulnerable PHP versions, particularly PHP 5.4.x versions before 5.4.24 and PHP 5.5.x versions before 5.5.8. The vulnerability classification aligns with CWE-94, which describes "Improper Control of Generation of Code ('Code Injection')" and represents a classic example of a code injection vulnerability that allows attackers to execute arbitrary commands on the target system.
The technical exploitation of this vulnerability occurs through manipulation of the content_class parameter, which is processed without adequate sanitization or validation checks. When an attacker crafts a malicious payload and submits it through this parameter, the system fails to properly escape or validate the input before using it in code execution contexts. This creates a pathway for remote attackers to inject and execute arbitrary PHP code on the server hosting the IPS Community Suite. The vulnerability is particularly dangerous because it allows attackers to gain full control over the affected system, potentially enabling them to access sensitive user data, modify forum content, install backdoors, or use the compromised server for further attacks. The attack vector is entirely remote, requiring no authentication or local access, making it highly attractive to threat actors seeking to compromise web applications at scale.
The operational impact of this vulnerability extends beyond simple code execution, as it fundamentally compromises the integrity and confidentiality of the affected systems. Organizations running vulnerable versions of the IPS Community Suite face significant risks including data breaches, service disruption, and potential regulatory compliance violations. The vulnerability's exploitation can lead to complete system compromise, allowing attackers to establish persistent access, exfiltrate user credentials and personal information, and use the compromised platform as a launching point for attacks on other systems within the network. Security professionals should note that this vulnerability affects not only the web application itself but also potentially exposes underlying database systems and associated infrastructure that relies on the forum platform for user management or content delivery.
Organizations should immediately implement mitigation strategies including upgrading to IPS Community Suite version 4.1.13 or later, which contains the necessary patches to address this vulnerability. Additionally, administrators must ensure their PHP installations are updated to versions that are not vulnerable to this specific attack vector, particularly upgrading PHP 5.4.x to 5.4.24 or later and PHP 5.5.x to 5.5.8 or later. Network-level mitigations such as implementing web application firewalls, restricting access to vulnerable endpoints, and monitoring for suspicious parameter usage should also be considered. The vulnerability demonstrates the critical importance of keeping both application software and underlying runtime environments updated, as highlighted by ATT&CK technique T1059.007 for "Command and Scripting Interpreter: PowerShell" and similar techniques that leverage code injection vulnerabilities. Organizations should also conduct thorough security assessments of their deployed IPS Community Suite installations to identify any potential exploitation attempts and implement proper logging and monitoring mechanisms to detect unauthorized access attempts.