Vulnerability in Cisco Nx-Os Software

CVE-2021-1587

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. An attacker could exploit this vulnerability by sending crafted packets, including the TRILL OAM EtherType of 0x8902, 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. Note: The NGOAM feature is disabled by default.

Published · last modified .

CVSS v3 metric

CVSS v3 base score 8.6 (High). Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:C/C:N/I:N/A:H.

EPSS exploit prediction

EPSS: 0.017 (76.6th percentile), scored .

Low probability of exploitation in the next 30 days, but still tracked. 77th percentile — 76.6% of CVEs in the catalogue have a lower EPSS than this one. How to read EPSS.

EPSS trend (30 days)EPSS over the last 30 days for CVE-2021-1587: held from 0.017 to 0.017.

EPSS over last 30 days · oldest: 0.017 · newest: 0.017 · change: 0.000

Affected products

Weakness classification (CWE)

References

Frequently asked questions

What is CVE-2021-1587?
CVE-2021-1587 is a high-severity vulnerability in Cisco Nx-Os Software, classified under CWE-115. CVSS score: 8.6/10. Published 2021-08-25.
How severe is CVE-2021-1587?
High severity. CVSS v3 base score is 8.6 out of 10.