CVE-2021-1239

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.

• CWE-79
• CWE-79

• https://tools.cisco.com/security/center/content/CiscoSecurityAdvisory/cisco-sa-fmc-stored-xss-djKfCzf2Vendor Advisory
• https://tools.cisco.com/security/center/content/CiscoSecurityAdvisory/cisco-sa-fmc-stored-xss-djKfCzf2Vendor Advisory

Published

Jan 13, 2021

Last Modified

Jun 17, 2026

Status

Modified

• How Strix found a critical auth bypass in etcdStrix autonomously discovered a critical authentication bypass in etcd, later designated CVE-2026-33413.
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