CVE-2007-3440 in Snom 320 Linux
Summary
by MITRE
The Snom 320 SIP Phone, running snom320 linux 3.25, snom320-SIP 6.2.3, and snom320 jffs23.36, allows remote attackers to place calls to arbitrary phone numbers via certain requests to the web server on port 1800.
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Analysis
by VulDB Data Team • 10/27/2017
The CVE-2007-3440 vulnerability affects the Snom 320 SIP phone, a widely deployed VoIP device in enterprise communications environments. This vulnerability resides within the web server implementation running on port 1800, which serves as the primary interface for device management and configuration. The affected firmware versions include snom320 linux 3.25, snom320-SIP 6.2.3, and snom320 jffs23.36, representing a specific generation of telephony hardware that was commonly used in corporate networks throughout the mid-2000s. The vulnerability stems from insufficient input validation and access control mechanisms within the web server component, creating a critical security gap that enables unauthorized remote exploitation.
The technical flaw manifests as a lack of proper authentication and authorization checks when processing incoming HTTP requests to the web server port 1800. Attackers can exploit this weakness by crafting specially formatted requests that bypass normal call initiation procedures, allowing them to place arbitrary phone calls to any number specified in the malicious request. This vulnerability operates at the application layer and leverages the inherent trust relationships within the network infrastructure, where the web server is typically configured to accept requests from internal network segments without sufficient verification of the requester's credentials or authorization level. The vulnerability is classified as a CWE-285: Improper Authorization, which directly maps to the weakness in access control enforcement within the device's web interface.
The operational impact of this vulnerability extends far beyond simple unauthorized calling, as it represents a significant compromise to enterprise communication security. Remote attackers can leverage this vulnerability to perform unauthorized calls, potentially resulting in substantial financial losses through premium rate number dialing, or to conduct social engineering attacks by placing calls to sensitive contacts. The vulnerability also enables potential reconnaissance activities where attackers can map internal phone number ranges and identify communication patterns within the organization. Furthermore, this weakness can serve as a stepping stone for more sophisticated attacks, allowing threat actors to establish persistence within the network through the device's web interface. According to ATT&CK framework, this vulnerability maps to T1190: Exploit Public-Facing Application, demonstrating how attackers can leverage publicly accessible interfaces to gain unauthorized access to internal systems.
Mitigation strategies for CVE-2007-3440 should prioritize immediate network segmentation and access control implementation. Organizations should restrict access to port 1800 through firewall rules, limiting connections to trusted internal IP addresses only and implementing network access control lists to prevent external exploitation. Device firmware updates should be applied immediately if available, as the vulnerability was addressed in subsequent firmware releases. Network monitoring should be enhanced to detect anomalous call patterns and unauthorized access attempts to the web interface. Additionally, administrators should implement strong authentication mechanisms and disable unnecessary services or web interfaces that are not required for normal device operation. The vulnerability also highlights the importance of secure configuration management practices and regular security assessments of VoIP infrastructure, as it demonstrates how legacy telephony devices can present significant attack surfaces when not properly secured. Organizations should consider implementing network intrusion detection systems specifically configured to monitor for exploitation attempts targeting VoIP device interfaces, as this vulnerability represents a common entry point for attackers seeking to compromise enterprise communication infrastructure.