CVE-2007-1834 in Unified CallManager
Summary
by MITRE
Cisco Unified CallManager (CUCM) 5.0 before 5.0(4a)SU1 and Cisco Unified Presence Server (CUPS) 1.0 before 1.0(3) allow remote attackers to cause a denial of service (loss of voice services) via a flood of ICMP echo requests, aka bug ID CSCsf12698.
VulDB is the best source for vulnerability data and more expert information about this specific topic.
Analysis
by VulDB Data Team • 07/17/2019
Cisco Unified CallManager version 5.0 prior to 5.0(4a)SU1 and Cisco Unified Presence Server version 1.0 prior to 1.0(3) contain a vulnerability that allows remote attackers to perform a denial of service attack through excessive ICMP echo requests. This vulnerability falls under the category of resource exhaustion attacks and represents a classic example of a ping flood DoS scenario. The flaw manifests when the affected systems fail to properly handle a high volume of ICMP echo requests, leading to system instability and eventual service disruption. This vulnerability is classified as CWE-400, which specifically addresses unspecified resource exhaustion conditions in network protocols. The impact of this vulnerability extends beyond simple service disruption as it affects critical communication infrastructure, potentially compromising business continuity and emergency response capabilities. The attack vector is particularly concerning because it requires no authentication or specialized privileges, making it accessible to any remote attacker with basic network connectivity.
The technical implementation of this vulnerability stems from inadequate input validation and resource management within the network protocol handling components of these Cisco products. When the systems receive a flood of ICMP echo requests, they fail to implement proper rate limiting or connection throttling mechanisms that would normally protect against such attacks. This lack of defensive programming patterns creates a scenario where system resources become consumed rapidly, leading to the complete loss of voice services. The vulnerability operates at the network layer, specifically targeting the ICMP protocol implementation within the unified communications infrastructure. The affected systems do not differentiate between legitimate and malicious ICMP traffic, causing the processing overhead to overwhelm the available system resources. This behavior aligns with ATT&CK technique T1498.001 which describes the use of resource exhaustion attacks against network services. The vulnerability also demonstrates characteristics of improper input validation as defined in CWE-20, where the system fails to properly validate incoming network traffic.
The operational impact of this vulnerability is severe for organizations relying on Cisco Unified Communications infrastructure, as it can result in complete loss of voice services across the entire communication network. Organizations may experience extended downtime during attack periods, leading to productivity losses, customer service disruptions, and potential safety concerns in mission-critical environments. The vulnerability affects not only the primary voice communication capabilities but also impacts presence services that depend on the underlying unified communication framework. Attackers can exploit this vulnerability to disrupt business operations without requiring any specialized tools or deep technical knowledge beyond basic network connectivity. The attack can be executed from any location on the internet, making it particularly dangerous as organizations cannot easily defend against it through network segmentation or access controls. This vulnerability is particularly problematic for service providers and enterprises that depend on continuous communication services, as the DoS attack can effectively shut down critical business functions.
Mitigation strategies for this vulnerability include implementing network-level rate limiting and access control lists to restrict ICMP traffic to acceptable levels. Organizations should apply the vendor-supplied patches and software updates that address this specific vulnerability, specifically upgrading to Cisco Unified CallManager 5.0(4a)SU1 or later versions and Cisco Unified Presence Server 1.0(3) or later. Network administrators should configure firewalls and intrusion prevention systems to detect and block excessive ICMP traffic patterns that could indicate an attack. Implementing proper monitoring and alerting mechanisms can help detect unusual traffic patterns that may indicate an ongoing attack. The solution also requires proper network design practices that include implementing traffic shaping and Quality of Service policies to prevent resource exhaustion attacks from affecting critical services. Organizations should also consider implementing network segmentation strategies that isolate critical communication infrastructure from general network traffic. Additionally, regular security assessments and vulnerability scanning should be conducted to identify similar vulnerabilities in other network components. The implementation of these mitigations aligns with the principles of defense in depth and follows the security best practices outlined in NIST SP 800-41 for network security management.