CVE-2017-3860 in IOS
Summary
by MITRE
Multiple vulnerabilities in the EnergyWise module of Cisco IOS (12.2 and 15.0 through 15.6) and Cisco IOS XE (3.2 through 3.18) could allow an unauthenticated, remote attacker to cause a buffer overflow condition or a reload of an affected device, leading to a denial of service (DoS) condition. These vulnerabilities are due to improper parsing of crafted EnergyWise packets destined to an affected device. An attacker could exploit these vulnerabilities by sending crafted EnergyWise packets to be processed by an affected device. An exploit could allow the attacker to cause a buffer overflow condition or a reload of the affected device, leading to a DoS condition. Cisco IOS Software and Cisco IOS XE Software support EnergyWise for IPv4 communication. Only IPv4 packets destined to a device configured as an EnergyWise domain member can trigger these vulnerabilities. IPv6 packets cannot be used to trigger these vulnerabilities. Cisco Bug ID CSCur29331.
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Analysis
by VulDB Data Team • 12/21/2020
The vulnerability identified as CVE-2017-3860 represents a critical denial of service weakness within Cisco's networking infrastructure software, specifically affecting the EnergyWise module implementation in both Cisco IOS and Cisco IOS XE operating systems. This flaw exists in versions spanning from Cisco IOS 12.2 through 15.6 and Cisco IOS XE 3.2 through 3.18, creating a substantial attack surface across multiple generations of Cisco's network operating systems. The EnergyWise module, designed to facilitate energy management protocols within network environments, becomes a vector for exploitation when processing improperly formatted packets, fundamentally compromising the stability and availability of affected network devices.
The technical root cause of this vulnerability lies in inadequate input validation and buffer management within the EnergyWise packet processing mechanism. When an attacker crafts and transmits specially formatted EnergyWise packets specifically designed for IPv4 communication, the system fails to properly validate packet boundaries and memory allocation, resulting in buffer overflow conditions. This improper parsing behavior stems from insufficient bounds checking during packet header and payload processing, allowing maliciously constructed data to overwrite adjacent memory locations. The vulnerability manifests through two distinct operational outcomes: either a controlled buffer overflow that can be leveraged to execute arbitrary code or an uncontrolled device reload that results in complete service disruption, both of which constitute successful denial of service attacks.
The operational impact of CVE-2017-3860 extends beyond simple network disruption, as it provides attackers with a mechanism to systematically compromise network availability across multiple device types simultaneously. The vulnerability's requirement for IPv4 packets destined to EnergyWise domain members creates a targeted attack vector that can be exploited in environments where EnergyWise functionality is enabled, potentially affecting enterprise networks, service provider infrastructures, and critical infrastructure deployments. The attack can be executed remotely without authentication, making it particularly dangerous as it requires no prior access credentials or network privileges. The resulting device reloads create cascading effects in network topology, potentially disrupting services, breaking network connectivity, and requiring manual intervention to restore normal operations, with potential business continuity implications.
Security mitigations for this vulnerability should focus on immediate patch deployment through Cisco's official security advisories, as the manufacturer released patches addressing the buffer overflow conditions in the EnergyWise module. Network administrators should consider implementing access control lists to filter EnergyWise traffic at network boundaries, particularly blocking IPv4 packets destined for EnergyWise ports. The implementation of network segmentation and the disabling of EnergyWise functionality on affected devices where it is not required provides additional defense-in-depth measures. Organizations should also monitor network traffic for unusual EnergyWise packet patterns and implement intrusion detection systems to identify potential exploitation attempts. This vulnerability aligns with CWE-121, which describes heap-based buffer overflow conditions, and maps to ATT&CK technique T1499.004 for network denial of service attacks, emphasizing the need for robust input validation and proper memory management practices in network protocol implementations.