CVE-2021-34763: Cisco Firepower Management Center Software Cross-Site Scripting and Open Redirect Vulnerabilities

Severity: medium (CVSS 4.8 v3.1)
Exploited in the wild: not listed in CISA KEV
EPSS: 0.5% probability of exploitation in the next 30 days
Public exploit or detection template: none known
Published: 2021-10-27 · updated 2026-08-11
Weakness: CWE-601

Description

Multiple vulnerabilities in the web-based management interface of Cisco Firepower Management Center (FMC) Software could allow an attacker to execute a cross-site scripting (XSS) attack or an open redirect attack. For more information about these vulnerabilities, see the Details section of this advisory.

Affected products

Cisco Firepower Management Center Virtual Appliance: 6.1.0, 6.2.0, 6.2.3, 6.3.0, 6.4.0, 6.5.0 (+5)
Cisco Firepower Threat Defense Software: before 6.4.0.13; from 6.5.0 before 6.6.5; from 6.7.0 before 6.7.0.3 — fixed in 6.4.0.13, 6.6.5, 6.7.0.3
Cisco Sourcefire Defense Center: 6.1.0, 6.2.0, 6.2.3, 6.3.0, 6.4.0, 6.5.0 (+5)

How to fix

Upgrade to a fixed version: Cisco Firepower Threat Defense Software 6.4.0.13, 6.6.5, 6.7.0.3. Check the vendor advisory for mitigations.

References

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