Known exploited vulnerability

CVE-2020-3569

Cisco IOS XR Software DVMRP Memory Exhaustion Vulnerability

What is affected

Vendor Cisco
Product IOS XR
Weakness CWE-400

The vulnerability

Cisco IOS XR Distance Vector Multicast Routing Protocol (DVMRP) incorrectly handles Internet Group Management Protocol (IGMP) packets. Exploitation could allow an unauthenticated, remote attacker to immediately crash the IGMP process or make it consume available memory and eventually crash.

Required action

Apply updates per vendor instructions.

US federal civilian agencies were required to act by 3 May 2022 under BOD 22-01. The deadline is a compliance date, not a measure of severity — it says nothing about how dangerous the flaw is to anyone else.

Where this comes from

Every field on this page is taken from the CISA Known Exploited Vulnerabilities catalog, last synced 11 Nov 2026, 21:30. Nothing here is our own assessment. For the technical scoring, see the NVD record below.

NVD record ↗ CVE.org record ↗

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