PT-2021-4501 · Cisco · Cisco Nx-Os+1

Published 2021-08-25 · Updated 2021-09-02 · CVE-2021-1587

Positive Technologies (AI Summary)

CVSS v3.1

8.6

High

Base vector

AV:N/AC:L/PR:N/UI:N/S:C/C:N/I:N/A:H

Name of the Vulnerable Software and Affected Versions Cisco NX-OS Software (affected versions not specified)

Description A vulnerability in the VXLAN Operation, Administration, and Maintenance (OAM) feature of Cisco NX-OS Software, known as NGOAM, could allow an unauthenticated, remote attacker to cause a denial of service (DoS) condition on an affected device. This vulnerability is due to improper handling of specific packets with a Transparent Interconnection of Lots of Links (TRILL) OAM EtherType, such as the TRILL OAM EtherType of 0x8902. An attacker could exploit this vulnerability by sending crafted packets to a device that is part of a VXLAN Ethernet VPN (EVPN) fabric. A successful exploit could allow the attacker to cause an affected device to experience high CPU usage and consume excessive system resources, which may result in overall control plane instability and cause the affected device to reload.

Recommendations At the moment, there is no information about a newer version that contains a fix for this vulnerability.

DoS

Weakness Enumeration

CWE-436

CWE-115

Related Identifiers

BDU:2021-05137

CVE-2021-1587

Affected Products

Cisco Nx-Os

Cisco Nexus

References · 7

• https://bdu.fstec.ru/vul/2021-05137 · Security Note
• https://nvd.nist.gov/vuln/detail/CVE-2021-1587 · Security Note
• https://sec.cloudapps.cisco.com/security/center/content/CiscoSecurityAdvisory/cisco-sa-nxos-ngoam-dos-LTDb9Hv · Vendor Advisory
• https://tools.cisco.com/security/center/content/CiscoSecurityAdvisory/cisco-sa-nxos-ngoam-dos-LTDb9Hv · Vendor Advisory
• https://safe-surf.ru/specialists/bulletins-nkcki/668962 · Security Note
• https://t.me/cvenotify/20103 · Telegram Post
• https://t.me/cvenotify/20597 · Telegram Post