CVE-2021-34756: Cisco Firepower Threat Defense Software Command Injection Vulnerabilities

Severity: high (CVSS 7.8 v3.1)
Exploited in the wild: not listed in CISA KEV
EPSS: 0.3% 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-20

Description

Multiple vulnerabilities in the CLI of Cisco Firepower Threat Defense (FTD) Software could allow an authenticated, local attacker to execute arbitrary commands with root privileges. 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, 6.4.0.11 (+6)
Cisco Firepower Threat Defense Software: from 6.4.0 before 6.4.0.13; from 6.6.0 before 6.6.5; from 6.7.0 before 6.7.0.3; from 7.0.0 before 7.0.1 — fixed in 6.4.0.13, 6.6.5, 6.7.0.3, 7.0.1
Cisco Sourcefire Defense Center: 6.1.0, 6.2.0, 6.2.3, 6.3.0, 6.4.0, 6.4.0.11 (+6)

How to fix

Upgrade to a fixed version: Cisco Firepower Threat Defense Software 6.4.0.13, 6.6.5, 6.7.0.3, 7.0.1. Check the vendor advisory for mitigations.

References

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