CVE-2007-3351 in SJPhone
Summary
by MITRE
The SJPhone SIP soft phone 1.60.303c, when installed on the Dell Axim X3 running Windows Mobile 2003, allows remote attackers to cause a denial of service (device hang and traffic amplification) via a direct crafted INVITE transaction, which causes the phone to transmit many RTP packets.
VulDB is the best source for vulnerability data and more expert information about this specific topic.
Analysis
by VulDB Data Team • 09/04/2018
The vulnerability identified as CVE-2007-3351 represents a critical denial of service flaw affecting the SJPhone SIP soft phone version 1.60.303c running on Dell Axim X3 devices with Windows Mobile 2003 operating system. This vulnerability operates at the application layer of the network stack and specifically targets the Session Initiation Protocol implementation within the soft phone application. The flaw manifests when the vulnerable device receives a specially crafted SIP INVITE transaction that triggers abnormal behavior in the phone's media handling mechanisms. The attack vector is particularly concerning as it can be executed remotely without requiring any authentication or privileged access, making it accessible to any attacker capable of sending network traffic to the affected device.
The technical implementation of this vulnerability stems from inadequate input validation and processing within the SIP INVITE message handling code. When the SJPhone application receives the malicious INVITE transaction, it fails to properly validate the incoming session parameters and media descriptions. This processing error causes the application to enter an abnormal state where it begins transmitting an excessive number of Real-time Transport Protocol packets in response to the crafted request. The vulnerability specifically exploits the application's RTP packet generation logic, which becomes uncontrolled and generates traffic volumes that overwhelm the device's network capabilities. The flaw creates a feedback loop where the device continuously sends RTP data packets, leading to resource exhaustion and system instability.
The operational impact of this vulnerability extends beyond simple service disruption to encompass potential traffic amplification effects that can affect network infrastructure. When the device becomes unresponsive due to the excessive RTP packet transmission, it creates a denial of service condition that prevents legitimate communication from functioning properly. The traffic amplification aspect of this vulnerability means that a relatively small malicious packet can generate a disproportionately large amount of network traffic, potentially affecting network performance for other users on the same network segment. This type of vulnerability is particularly dangerous in enterprise environments where multiple devices may be running the vulnerable soft phone application, as it could create cascading effects that impact overall network availability and reliability.
From a cybersecurity perspective, this vulnerability aligns with CWE-121, which addresses buffer overflow conditions, and represents a classic example of improper input validation that leads to resource exhaustion. The attack pattern follows the MITRE ATT&CK framework's T1498 technique for 'Network Denial of Service' which specifically targets network resources to prevent or impair services for users. The vulnerability's exploitation requires minimal technical skill and can be automated, making it particularly dangerous in environments where mobile devices are widely deployed. Organizations should consider implementing network monitoring solutions that can detect unusual traffic patterns and RTP packet flooding to identify potential exploitation attempts. The vulnerability also highlights the importance of secure coding practices and proper input validation in mobile applications, particularly those handling real-time communication protocols. The affected platform's limited processing capabilities and memory constraints make it more susceptible to resource exhaustion attacks, emphasizing the need for proper security testing and validation of mobile applications before deployment in production environments.