CVE-2020-3569highunder attackCWE-400

CVE-2020-3569: high-severity vulnerability in Cisco IOS XR Software

Cisco IOS XR Software DVMRP Memory Exhaustion Vulnerabilities

Published · Updated

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51Vexday Risk Score

Prioritize patching. It under exploitation confirmed by CISA.

ssvc Actcvss 8.6epss 3.3%
from disclosure to weapon
Published on NVDSep 23
CISA KEV+406d
Action required by CISAfederal deadline: 2022-05-03

Apply updates per vendor instructions.

In short

Cisco IOS XR devices running DVMRP can crash or run out of memory when they receive specially crafted network messages. An attacker on the internet can send these messages without needing a password, potentially disrupting network routing and other services.

Technical detail

Unauthenticated remote attacker can trigger immediate IGMP process crash or memory exhaustion via malformed IGMP packets in DVMRP feature on Cisco IOS XR. Improper packet handling leads to resource depletion and potential destabilization of routing protocols and other critical processes.

Summary generated and translated by AI from the official description.

The full analysis of this CVE is available in Portuguese →

Multiple vulnerabilities in the Distance Vector Multicast Routing Protocol (DVMRP) feature of Cisco IOS XR Software could allow an unauthenticated, remote attacker to either immediately crash the Internet Group Management Protocol (IGMP) process or make it consume available memory and eventually crash. The memory consumption may negatively impact other processes that are running on the device. These vulnerabilities are due to the incorrect handling of IGMP packets. An attacker could exploit these vulnerabilities by sending crafted IGMP traffic to an affected device. A successful exploit could allow the attacker to immediately crash the IGMP process or cause memory exhaustion, resulting in other processes becoming unstable. These processes may include, but are not limited to, interior and exterior routing protocols. Cisco will release software updates that address these vulnerabilities.
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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