CVE-2020-3566highunder attackCWE-400

CVE-2020-3566: high-severity vulnerability in Cisco IOS XR Software

Cisco IOS XR Software DVMRP Memory Exhaustion Vulnerability

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51Vexday Risk Score

Prioritize patching. It under exploitation confirmed by CISA.

ssvc Actcvss 8.6epss 3.7%
from disclosure to weapon
Published on NVDAug 29
CISA KEV+431d
Action required by CISAfederal deadline: 2022-05-03

Apply updates per vendor instructions.

In short

A flaw in Cisco IOS XR's DVMRP feature allows an attacker to send specially crafted network packets that consume all available memory on the device, causing it to become unstable or stop working properly.

Technical detail

An unauthenticated remote attacker can exploit insufficient queue management in IGMP packet processing within DVMRP to exhaust process memory on vulnerable Cisco IOS XR devices, leading to denial of service and disruption of routing protocols. The attack requires no authentication and can be executed by sending crafted IGMP traffic to an affected device.

Summary generated and translated by AI from the official description.

The full analysis of this CVE is available in Portuguese →

A vulnerability in the Distance Vector Multicast Routing Protocol (DVMRP) feature of Cisco IOS XR Software could allow an unauthenticated, remote attacker to exhaust process memory of an affected device. The vulnerability is due to insufficient queue management for Internet Group Management Protocol (IGMP) packets. An attacker could exploit this vulnerability by sending crafted IGMP traffic to an affected device. A successful exploit could allow the attacker to cause memory exhaustion, resulting in instability of other processes. These processes may include, but are not limited to, interior and exterior routing protocols. Cisco will release software updates that address this vulnerability.
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:C/C:N/I:N/A:H
Affected products
Cisco · Cisco IOS XR Software
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