CVE-2014-1903 in FreePBX
Summary
by MITRE
admin/libraries/view.functions.php in FreePBX 2.9 before 2.9.0.14, 2.10 before 2.10.1.15, 2.11 before 2.11.0.23, and 12 before 12.0.1alpha22 does not restrict the set of functions accessible to the API handler, which allows remote attackers to execute arbitrary PHP code via the function and args parameters to admin/config.php.
VulDB is the best source for vulnerability data and more expert information about this specific topic.
Analysis
by VulDB Data Team • 02/01/2025
The vulnerability identified as CVE-2014-1903 represents a critical remote code execution flaw within the FreePBX telephony system that affects multiple version branches including 2.9, 2.10, 2.11, and 12. This vulnerability stems from insufficient input validation and access control mechanisms within the API handler component, specifically in the admin/libraries/view.functions.php file. The flaw allows remote attackers to manipulate the function and args parameters through the admin/config.php endpoint, thereby enabling arbitrary PHP code execution on the affected system. This represents a classic command injection vulnerability that can be exploited without authentication, making it particularly dangerous in networked environments where telephony systems are exposed to external networks.
The technical exploitation of this vulnerability occurs through the improper sanitization of user-supplied input parameters within the API handler. When attackers submit malicious function names and arguments through the admin/config.php interface, the system fails to properly validate or restrict which PHP functions can be executed, allowing direct invocation of dangerous system commands. This flaw aligns with CWE-94, which describes improper control of generation of code, specifically addressing situations where user-controllable data is used to construct executable code without proper validation. The vulnerability demonstrates weak input filtering and inadequate sandboxing of API endpoints, creating an attack surface where arbitrary code execution becomes possible through parameter manipulation.
The operational impact of this vulnerability extends far beyond simple code execution, as it can enable attackers to completely compromise the FreePBX system and potentially the entire underlying network infrastructure. Once exploited, attackers can gain full administrative control over the telephony system, allowing them to modify call routing, access voicemail systems, intercept communications, and potentially pivot to other systems within the network. This vulnerability particularly affects organizations that rely on FreePBX for voice communications, as it can lead to significant security breaches including eavesdropping on sensitive conversations, unauthorized access to business communications, and potential data exfiltration. The attack vector is particularly concerning because it requires no authentication, making it accessible to anyone who can reach the web interface.
Organizations should implement immediate mitigations including applying the vendor-provided security patches that address this vulnerability in all affected FreePBX versions. The recommended approach involves upgrading to the patched versions mentioned in the CVE description, specifically versions 2.9.0.14, 2.10.1.15, 2.11.0.23, and 12.0.1alpha22. Network-level protections should include restricting access to the FreePBX web interface through firewalls and implementing proper access controls to limit who can reach the admin/config.php endpoint. Additionally, organizations should consider implementing web application firewalls and monitoring for suspicious API parameter patterns. According to ATT&CK framework, this vulnerability maps to T1059.007 for PHP code execution and T1071.001 for application layer protocol usage, indicating that defensive measures should focus on both network perimeter controls and application-level security monitoring to detect and prevent exploitation attempts.