CVE-2016-1370 in Prime Network Analysis Module
Summary
by MITRE
Cisco Prime Network Analysis Module (NAM) before 6.2(1-b) miscalculates IPv6 payload lengths, which allows remote attackers to cause a denial of service (mond process crash and monitoring outage) via crafted IPv6 packets, aka Bug ID CSCuy37324.
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Analysis
by VulDB Data Team • 10/15/2024
The vulnerability identified as CVE-2016-1370 affects Cisco Prime Network Analysis Module version 6.2(1-b) and earlier, representing a critical flaw in IPv6 packet processing that can lead to significant network disruption. This issue manifests when the NAM system encounters crafted IPv6 packets with malformed payload length fields, causing the mond process to crash and resulting in complete monitoring outages for affected networks. The vulnerability resides in the network analysis module's handling of IPv6 protocol headers, specifically in how it calculates and validates payload lengths during packet inspection processes.
The technical root cause of this vulnerability stems from improper validation of IPv6 payload length fields within the NAM's packet processing engine. When the system receives IPv6 packets containing manipulated or invalid payload length values, the miscalculation causes the mond monitoring process to enter an unstable state leading to application termination and subsequent service disruption. This flaw operates at the network protocol level, specifically targeting the IPv6 implementation within Cisco's network monitoring infrastructure, making it particularly dangerous in environments where continuous network visibility is critical for operations. The vulnerability can be exploited remotely without authentication, making it accessible to attackers anywhere on the network.
The operational impact of this vulnerability extends beyond simple service disruption, creating cascading effects that can compromise network monitoring capabilities and potentially mask other security incidents. When the mond process crashes, the entire monitoring function of the NAM device becomes unavailable, leaving network administrators without visibility into network traffic patterns, performance metrics, and potential security threats. This outage can persist until manual intervention occurs to restart the affected processes or until the device is rebooted, creating windows of operational vulnerability that attackers could exploit. The disruption affects not only the immediate monitoring capabilities but also the broader network management infrastructure that relies on this data for decision-making processes.
Organizations should implement immediate mitigations including applying the vendor-provided security patches and updates that address the IPv6 payload length calculation error in the NAM software. Network segmentation and access control measures can help limit exposure by restricting direct network access to affected devices. Monitoring systems should be configured to detect and alert on unusual process restart patterns or monitoring outages that could indicate exploitation attempts. Security teams should also consider implementing network-based intrusion detection systems that can identify and block malformed IPv6 traffic patterns associated with this vulnerability. This remediation approach aligns with the principle of least privilege and defense in depth strategies recommended in cybersecurity frameworks. The vulnerability demonstrates the importance of proper input validation and error handling in network infrastructure components, particularly those handling protocol parsing functions. According to CWE guidelines, this represents a classic case of improper input validation and error handling that can lead to denial of service conditions. The ATT&CK framework categorizes this vulnerability under the technique of service stoppage, where adversaries can disrupt network monitoring capabilities to hinder incident response and security operations. Organizations should also consider implementing network access controls to prevent unauthorized access to network analysis modules and establish baseline monitoring procedures that can quickly detect process failures and system outages.