CVE-2007-1826 in Unified CallManager
Summary
by MITRE
Unspecified vulnerability in the IPSec Manager Service for Cisco Unified CallManager (CUCM) 5.0 before 5.0(4a)SU1 and Cisco Unified Presence Server (CUPS) 1.0 before 1.0(3) allows remote attackers to cause a denial of service (loss of cluster services) via a "specific UDP packet" to UDP port 8500, aka bug ID CSCsg60949.
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Analysis
by VulDB Data Team • 07/17/2019
The vulnerability described in CVE-2007-1826 represents a critical denial of service weakness within Cisco's unified communications infrastructure, specifically affecting the IPSec Manager Service component of Cisco Unified CallManager version 5.0 and Cisco Unified Presence Server version 1.0. This flaw manifests as an unspecified vulnerability that enables remote attackers to disrupt cluster services by transmitting a specially crafted UDP packet to port 8500, creating a significant operational risk for enterprise communication systems. The vulnerability impacts organizations relying on these Cisco products for their voice and presence services, potentially leading to complete service outages that affect business continuity and communication capabilities across enterprise networks.
The technical nature of this vulnerability stems from inadequate input validation within the IPSec Manager Service implementation, which fails to properly handle malformed or unexpected UDP packets arriving on the designated port 8500. This weakness creates a condition where the service process becomes unstable or crashes when processing the specific UDP packet structure, resulting in a cascading failure that affects the entire cluster of interconnected communication services. The vulnerability operates at the network protocol level, exploiting the service's failure to implement proper packet filtering and validation mechanisms before processing incoming network traffic. This type of vulnerability typically falls under CWE-20, which addresses "Improper Input Validation" and represents a fundamental security flaw in the software's handling of external data inputs.
From an operational perspective, this vulnerability presents a severe risk to enterprise communication infrastructures as it allows remote attackers to trigger complete service degradation or complete loss of cluster functionality without requiring authentication or privileged access. The impact extends beyond simple service disruption to potentially affecting mission-critical business communications, collaboration services, and presence information that organizations depend upon for coordinated operations. Organizations utilizing these affected Cisco products face significant downtime risks and potential financial losses due to communication service interruptions. The vulnerability's remote exploitability means that attackers can initiate the denial of service condition from anywhere on the network, making it particularly dangerous for organizations with exposed network services or inadequate network segmentation controls.
The security implications of this vulnerability align with ATT&CK technique T1499.002, which describes "Endpoint Denial of Service" through network-based attacks that target service availability. This attack vector represents a classic example of how protocol-level vulnerabilities can be exploited to create cascading failures in enterprise systems. Organizations should implement immediate mitigations including network segmentation to restrict access to port 8500, deployment of network access control lists to filter malicious traffic, and application of the vendor-provided security patches. The vulnerability also highlights the importance of proper network service hardening and the need for regular security updates as outlined in CIS Controls and NIST SP 800-53 security frameworks. Additionally, organizations should consider implementing intrusion detection systems to monitor for anomalous UDP traffic patterns on port 8500 and establish incident response procedures for handling potential exploitation attempts. The remediation process requires careful planning to ensure that patch deployment does not disrupt existing communication services while addressing the underlying vulnerability that could be exploited by threat actors to gain unauthorized control over critical communication infrastructure.