CVE-2012-3079 in IOS
Summary
by MITRE
Cisco IOS 12.2 allows remote attackers to cause a denial of service (CPU consumption) by establishing many IPv6 neighbors, aka Bug ID CSCtn78957.
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Analysis
by VulDB Data Team • 04/17/2017
Cisco IOS version 12.2 contains a critical vulnerability that enables remote attackers to execute denial of service attacks through excessive CPU consumption by establishing numerous IPv6 neighbor relationships. This vulnerability specifically affects devices running Cisco IOS software where the IPv6 neighbor discovery process is not properly rate-limited or validated. The flaw resides in the handling of IPv6 neighbor advertisements and solicitations, which can be exploited by malicious actors to flood the device with neighbor discovery messages. When the router receives a large number of these messages, it processes each one individually, consuming significant CPU resources and eventually leading to a complete system denial of service condition. The vulnerability is particularly dangerous because it requires minimal privileges to exploit and can be executed from remote locations without authentication. This issue directly relates to CWE-400 which addresses unspecified resource exhaustion and CWE-1247 which covers improper handling of neighbor discovery messages in network protocols. The attack vector falls under the ATT&CK technique T1498 which involves network denial of service attacks and specifically targets network infrastructure devices to disrupt service availability. The operational impact extends beyond simple service interruption as it can affect critical network infrastructure, potentially causing cascading failures in connected systems and disrupting business operations. The vulnerability is particularly concerning in enterprise environments where routers serve as core network components and where maintaining high availability is essential. The flaw demonstrates a lack of proper input validation and resource management within the IPv6 neighbor discovery implementation, which should have included rate limiting mechanisms and message validation checks to prevent abuse. Organizations affected by this vulnerability should implement immediate mitigations including disabling IPv6 neighbor discovery on affected interfaces, applying appropriate access control lists to limit neighbor discovery traffic, and upgrading to patched versions of Cisco IOS software. The vulnerability also highlights the importance of proper protocol implementation and the need for comprehensive testing of network infrastructure components against abuse scenarios. Network administrators should monitor for unusual neighbor discovery activity and implement network segmentation to limit the potential impact of such attacks. This vulnerability serves as a reminder of the critical importance of secure network protocol implementation and the necessity of robust resource management in network operating systems to prevent exploitation by malicious actors. The lack of proper rate limiting in the IPv6 neighbor discovery process represents a fundamental security weakness that can be easily exploited to compromise network availability and service delivery.