CVE-2007-3322 in 4602SW IP Phone
Summary
by MITRE
The Avaya 4602 SW IP Phone (Model 4602D02A) with 2.2.2 and earlier SIP firmware uses a constant media port number for calls, which allows remote attackers to cause a denial of service (audio quality loss) via a flood of packets to the RTP port.
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Analysis
by VulDB Data Team • 07/20/2021
The vulnerability identified as CVE-2007-3322 affects the Avaya 4602 SW IP Phone model 4602D02A running SIP firmware version 2.2.2 and earlier. This issue represents a significant security weakness in voice communication systems that operates at the network protocol level. The flaw stems from the phone's implementation of the Session Initiation Protocol which governs multimedia communication sessions including voice and video calls. The specific technical implementation error manifests in the phone's handling of Real-time Transport Protocol (RTP) media streams during active calls. The phone consistently uses the same media port number for all outgoing and incoming audio streams, creating a predictable and static network endpoint that can be easily targeted by malicious actors.
The operational impact of this vulnerability extends beyond simple service disruption to encompass substantial degradation of audio quality during voice communications. Attackers can exploit this predictable port behavior by flooding the designated RTP port with excessive packets, causing buffer overflows or resource exhaustion within the phone's media processing capabilities. This attack vector aligns with the common pattern of denial of service attacks that target network services by overwhelming them with traffic. The consistent use of a fixed port number violates fundamental security principles of network service design, as it eliminates the randomness that typically helps prevent predictable attack patterns. This vulnerability is particularly concerning in enterprise environments where VoIP systems form the backbone of business communication infrastructure, as it can lead to complete communication breakdowns during critical business operations.
The technical flaw in the Avaya 4602 phone implementation directly corresponds to weakness categories identified in the Common Weakness Enumeration framework, specifically relating to predictable network resource usage and inadequate randomization of communication endpoints. This vulnerability can be categorized under CWE-1032 which deals with inadequate randomization of network resources, and CWE-400 which addresses resource exhaustion vulnerabilities. The attack methodology follows patterns described in the MITRE ATT&CK framework under the T1498 technique for network denial of service attacks, where adversaries leverage predictable network behavior to disrupt services. The phone's inability to dynamically assign or randomize RTP port numbers creates an exploitable condition that can be automated and scaled across multiple targets within a network. Organizations using this phone model face significant risk of both intentional disruption attacks and accidental network congestion that can severely impact business continuity and communication reliability.
Mitigation strategies for this vulnerability require immediate firmware updates from Avaya to address the predictable port usage behavior. Network administrators should implement traffic filtering rules to limit the volume of packets that can reach the designated RTP ports, though this approach only provides partial protection. The most effective long-term solution involves upgrading to firmware versions that properly randomize media port assignments for each call session, following established security practices for VoIP implementations. Additional defensive measures include network segmentation to isolate VoIP traffic, implementing quality of service policies to prioritize legitimate voice traffic, and deploying intrusion detection systems that can identify unusual packet patterns targeting the vulnerable port numbers. Organizations should also conduct regular vulnerability assessments to identify other legacy VoIP devices that may exhibit similar predictable behavior patterns and ensure comprehensive network security monitoring for potential exploitation attempts.