CVE-2020-3479

MEDIUM

Cisco IOS and IOS XE - Unauthenticated Denial of Service via Malformed EVPN BGP Update Messages

Title source: llm
STIX 2.1

Description

A vulnerability in the implementation of Multiprotocol Border Gateway Protocol (MP-BGP) for the Layer 2 VPN (L2VPN) Ethernet VPN (EVPN) address family in Cisco IOS Software and Cisco IOS XE Software could allow an unauthenticated, remote attacker to cause a denial of service (DoS) condition. The vulnerability is due to incorrect processing of Border Gateway Protocol (BGP) update messages that contain crafted EVPN attributes. An attacker could exploit this vulnerability by sending BGP update messages with specific, malformed attributes to an affected device. A successful exploit could allow the attacker to cause an affected device to crash, resulting in a DoS condition.

References (1)

Core 1

Scores

CVSS v3 6.1
EPSS 0.0039
EPSS Percentile 60.2%
Attack Vector NETWORK
CVSS:3.1/AV:N/AC:H/PR:N/UI:R/S:C/C:N/I:N/A:H

CISA SSVC

Vulnrichment
Exploitation none
Automatable no
Technical Impact partial

Details

CWE
CWE-400 CWE-20
Status published
Products (2)
cisco/ios
cisco/ios_xe
Published Sep 24, 2020
Tracked Since Feb 18, 2026