CVE-2014-2176 in IOS XR
Summary
by MITRE
Cisco IOS XR 4.1.2 through 5.1.1 on ASR 9000 devices, when a Trident-based line card is used, allows remote attackers to cause a denial of service (NP chip and line card reload) via malformed IPv6 packets, aka Bug ID CSCun71928.
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Analysis
by VulDB Data Team • 06/22/2021
Cisco IOS XR software running on ASR 9000 devices with Trident-based line cards contains a vulnerability that enables remote attackers to trigger a denial of service condition through the careful crafting of IPv6 packets. This vulnerability affects versions 4.1.2 through 5.1.1 of the IOS XR operating system, specifically when the network processing occurs on Trident-based line cards that utilize NP (Network Processor) chips for packet handling. The flaw manifests when the system receives malformed IPv6 packets that exploit a buffer handling error in the packet processing pipeline, causing the NP chip to crash and subsequently forcing a complete reload of the line card. The vulnerability is classified as a buffer overflow or memory corruption issue that falls under CWE-121, which addresses buffer overflow conditions where insufficient space is allocated for data, and also relates to CWE-125, which covers out-of-bounds read conditions. The attack vector requires remote network access to the affected device, making it particularly concerning for network infrastructure that is exposed to untrusted networks or internet-facing services. The impact of this vulnerability extends beyond simple service disruption as it can cause cascading failures in network operations, potentially affecting routing stability and overall network availability. The specific nature of the bug, identified as CSCun71928, indicates that it affects the network processor chip functionality within the Trident-based line cards, which are designed to handle high-speed packet processing for routing and switching operations. This vulnerability aligns with ATT&CK technique T1498, which covers network denial of service attacks that target network infrastructure devices, and also maps to T1595 which covers network device compromises that can lead to system instability and operational disruption. The exploitation of this vulnerability can result in significant operational impact including extended network downtime, potential data loss during service interruptions, and increased administrative overhead for system recovery and maintenance. Organizations running affected Cisco IOS XR versions should prioritize applying the relevant security patches provided by Cisco to address this vulnerability and prevent unauthorized remote exploitation that could lead to service degradation or complete network outages. The Trident-based line cards represent critical components in high-end network infrastructure, making this vulnerability particularly dangerous in enterprise and service provider environments where uptime and reliability are paramount for maintaining business operations and customer service levels.