CVE-2021-34761: Cisco Firepower Management Center Virtual Appliance

Medium severity, CVSS 6.0. EPSS: 0.2% chance of exploitation in the next 30 days.

A vulnerability in Cisco Firepower Threat Defense (FTD) Software could allow an authenticated, local attacker to overwrite or append arbitrary data to system files using root-level privileges. The attacker must have administrative credentials on the device. This vulnerability is due to incomplete validation of user input for a specific CLI command. An attacker could exploit this vulnerability by authenticating to the device with administrative privileges and issuing a CLI command with crafted user parameters. A successful exploit could allow the attacker to overwrite or append arbitrary data to system files using root-level privileges.

Affected products

• Cisco Firepower Management Center Virtual Appliance: version 6.2.3 only; version 6.4.0 only; version 6.6.1 only; version 6.7.0 only; version 7.0.0 only; version 7.1.0 only
• Cisco Secure Firewall Threat Defense: from 6.4.0, before 6.4.0.13 (fixed in 6.4.0.13); from 6.6.0, before 6.6.5 (fixed in 6.6.5); from 6.7.0, before 6.7.0.3 (fixed in 6.7.0.3); from 7.0.0, before 7.0.1 (fixed in 7.0.1)
• Cisco Sourcefire Defense Center: version 6.2.3 only; version 6.4.0 only; version 6.6.1 only; version 6.7.0 only; version 7.0.0 only; version 7.1.0 only

Published 2021-10-27. Last modified 2026-08-11.