CVE-2020-3398

Published Aug 27, 2020

Last updated 3 years ago

Overview

Description
A vulnerability in the Border Gateway Protocol (BGP) Multicast VPN (MVPN) implementation of Cisco NX-OS Software could allow an unauthenticated, remote attacker to cause a BGP session to repeatedly reset, causing a partial denial of service (DoS) condition due to the BGP session being down. The vulnerability is due to incorrect parsing of a specific type of BGP MVPN update message. An attacker could exploit this vulnerability by sending this BGP MVPN update message to a targeted device. A successful exploit could allow the attacker to cause the BGP peer connections to reset, which could lead to BGP route instability and impact traffic. The incoming BGP MVPN update message is valid but is parsed incorrectly by the NX-OS device, which could send a corrupted BGP update to the configured BGP peer. Note: The Cisco implementation of BGP accepts incoming BGP traffic from only explicitly configured peers. To exploit this vulnerability, an attacker must send a specific BGP MVPN update message over an established TCP connection that appears to come from a trusted BGP peer. To do so, the attacker must obtain information about the BGP peers in the trusted network of the affected system.
Source
ykramarz@cisco.com
NVD status
Analyzed

Risk scores

CVSS 3.1

Type
Primary
Base score
8.6
Impact score
4
Exploitability score
3.9
Vector string
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:C/C:N/I:N/A:H
Severity
HIGH

CVSS 3.0

Type
Secondary
Base score
8.6
Impact score
4
Exploitability score
3.9
Vector string
CVSS:3.0/AV:N/AC:L/PR:N/UI:N/S:C/C:N/I:N/A:H
Severity
HIGH

CVSS 2.0

Type
Primary
Base score
4.3
Impact score
2.9
Exploitability score
8.6
Vector string
AV:N/AC:M/Au:N/C:N/I:N/A:P

Weaknesses

nvd@nist.gov
CWE-20
ykramarz@cisco.com
CWE-20

Social media

Hype score
Not currently trending

Configurations