CVE-2002-0952 in ONS15454 Optical Transport Platform
Summary
by MITRE
Cisco ONS15454 optical transport platform running ONS 3.1.0 to 3.2.0 allows remote attackers to cause a denial of service (reset) by sending IP packets with non-zero Type of Service (TOS) bits to the Timing Control Card (TCC) LAN interface.
VulDB is the best source for vulnerability data and more expert information about this specific topic.
Analysis
by VulDB Data Team • 06/17/2019
The Cisco ONS 15454 optical transport platform represents a critical piece of telecommunications infrastructure designed for high-speed data transmission across fiber optic networks. This platform operates with specific firmware versions ranging from 3.1.0 through 3.2.0, which contain a significant vulnerability that affects the Timing Control Card (TCC) LAN interface. The vulnerability stems from insufficient input validation mechanisms within the platform's network processing stack, particularly concerning the handling of IP packet headers. When remote attackers exploit this weakness, they can trigger a complete system reset that effectively renders the transport platform non-operational.
The technical flaw manifests through the improper processing of Type of Service bits within IP packets. The TCC interface, which manages timing synchronization and control functions for the entire platform, fails to properly validate incoming TOS values before processing them. This weakness is classified as a buffer over-read or improper input validation issue that falls under the CWE-129 weakness category, specifically related to insufficient input validation. The vulnerability occurs because the system does not adequately sanitize the TOS field in incoming packets, allowing maliciously crafted packets with non-zero TOS bits to be processed without proper validation checks. When such packets reach the TCC LAN interface, the system's processing logic triggers an unexpected reset sequence that brings down the entire platform.
The operational impact of this vulnerability extends far beyond simple service disruption. The denial of service attack can cause significant network outages for telecommunications providers who rely on the ONS 15454 platform for their core infrastructure. The timing control card manages synchronization across multiple network elements, meaning a reset affects not just the individual device but potentially entire network segments that depend on precise timing coordination. This vulnerability directly maps to the ATT&CK technique T1499.004, which involves network denial of service attacks that target network infrastructure components. The attack requires minimal privileges and can be executed from remote locations, making it particularly dangerous for network operators who may not immediately detect such attacks. The reset mechanism effectively creates a cascading failure scenario where network synchronization is lost, potentially causing downstream equipment to malfunction or fail.
Mitigation strategies for this vulnerability involve several layers of defensive measures. Network administrators should implement ingress filtering to block packets with non-standard TOS values, particularly those with non-zero bits that are not part of the expected operational parameters. The most effective immediate solution involves applying Cisco's security patches that address the specific input validation flaw in the TCC interface processing code. Organizations should also consider implementing network segmentation to isolate the TCC interface from untrusted networks and deploy intrusion detection systems that can identify and alert on suspicious packet patterns targeting the TCC. The vulnerability demonstrates the critical importance of validating all network inputs and adheres to the principle of least privilege in network security design. Additionally, network operators should establish monitoring protocols that can detect anomalous reset patterns and implement automated response mechanisms to isolate affected components during attack scenarios.