CVE-2021-1238: Cisco Secure Firewall Management Center

Medium severity, CVSS 4.8. EPSS: 0.6% chance of exploitation in the next 30 days.

Multiple vulnerabilities in the web-based management interface of Cisco Firepower Management Center (FMC) could allow an authenticated, remote attacker to conduct a stored cross-site scripting (XSS) attack against a user of the interface of an affected system. The vulnerabilities exist because the web-based management interface does not properly validate user-supplied input. An attacker could exploit these vulnerabilities by persuading a user of the interface to click a crafted link. A successful exploit could allow the attacker to execute arbitrary script code in the context of the affected interface or access sensitive, browser-based information.

Affected products

• Cisco Secure Firewall Management Center: before 6.7.0 (fixed in 6.7.0)

Published 2021-01-13. Last modified 2026-06-17.