CVE-2021-34781
Cisco Firepower Management Center Virtual Appliance
A vulnerability in the processing of SSH connections for multi-instance deployments of Cisco Firepower Threat Defense (FTD) Software could allow an unauthenticated, remote attacker to cause a denial of service (DoS) condition on the affected device. This vulnerability is due to a lack of proper error handling when an SSH session fails to be established. An attacker could exploit this vulnerability by sending a high rate of crafted SSH connections to the instance. A successful exploit could allow the attacker to cause resource exhaustion, which causes a DoS condition on the affected device. The device must be manually reloaded to recover.
Exploitation status
- A vendor advisory or patch reference has been published.
What the metrics mean
- It is reachable over a network, without needing local access.
- For an attacker who can reach it, no special conditions are needed to exploit it.
- To exploit it, no account is needed.
- Beyond that, no action by a user is required.
Scoring
- CVSS
- 8.6 (v3.1)
- Vector
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:C/C:N/I:N/A:H- Weakness
- CWE-119
- Assigned by
- psirt@cisco.com
Dates
- Published
- 2021-10-27
- Last modified
- 2026-08-11
- Sources
- NVD
Affected products
- Cisco Firepower Management Center Virtual Appliance6.3.0, 6.4.0, 6.4.0.13, 6.5.0, 6.6.0, 6.7.0.3, 6.7.1, 7.0.0
- Cisco Secure Firewall Threat Defense6.3.0 - 6.4.0.13, 6.5.0 - 6.6.5, 6.7.0 - 6.7.0.3, 7.0.0 - 7.0.1
- Cisco Sourcefire Defense Center6.3.0, 6.4.0, 6.4.0.13, 6.5.0, 6.6.0, 6.7.0.3, 6.7.1, 7.0.0
As listed in the NVD configuration data. Not a statement about your estate.