CVE-2021-1518: Cisco Firepower Device Manager On-Box

High severity, CVSS 8.8. EPSS: 1.9% chance of exploitation in the next 30 days.

A vulnerability in the REST API of Cisco Firepower Device Manager (FDM) On-Box Software could allow an authenticated, remote attacker to execute arbitrary code on the underlying operating system of an affected device. This vulnerability is due to insufficient sanitization of user input on specific REST API commands. An attacker could exploit this vulnerability by sending a crafted HTTP request to the API subsystem of an affected device. A successful exploit could allow the attacker to execute arbitrary code on the underlying operating system. To exploit this vulnerability, an attacker would need valid low-privileged user credentials.

Affected products

• Cisco Firepower Device Manager On-Box: from 6.3.0, before 6.4.0 (fixed in 6.4.0); from 6.5.0, before 6.7.0.2 (fixed in 6.7.0.2)

Published 2021-07-22. Last modified 2026-06-17.