CVE-2020-3569: Cisco IOS XR Software DVMRP Memory Exhaustion Vulnerability

Vulnerability summary

CVE-2020-3569 is a high (CVSS 8.6) Uncontrolled Resource Consumption vulnerability in Cisco IOS XR. It is known to be exploited: CISA lists it, first on 03-11-2021. EPSS estimates a 3.32% chance of exploitation in the next 30 days, higher than 88.4% of scored vulnerabilities.

Timeline

1. 23-09-2020
   PublishedVulnerability first disclosed.
2. 03-11-2021
   Added to CISA KEVCisco IOS XR Software DVMRP Memory Exhaustion Vulnerability
3. 03-05-2022
   CISA remediation dueApply updates per vendor instructions.
4. 21-10-2025
   Last modifiedVulnerability information updated.

Description

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.

• CWE-400Uncontrolled Resource ConsumptionThe product does not properly control the allocation and maintenance of a limited resource.
• CWE-770Allocation of Resources Without Limits or ThrottlingThe product allocates a reusable resource or group of resources on behalf of an actor without imposing any intended restrictions on the size or number of resources that can be allocated.