HIGH · 8.6

CVE-2021-34781

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 o...

Vulnerability Description

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.

CVSS Score

8.6

HIGH

CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:C/C:N/I:N/A:H
Attack Vector
NETWORK
Attack Complexity
LOW
Privileges Required
NONE
User Interaction
NONE
Scope
CHANGED
Confidentiality
NONE
Integrity
NONE
Availability
HIGH

Affected Products

VendorProductVersions
CiscoFirepower Management Center Virtual Appliance6.3.0
CiscoFirepower Threat Defense>= 6.3.0, < 6.4.0.13
CiscoSourcefire Defense Center6.3.0

Related Weaknesses (CWE)

References

FAQ

What is CVE-2021-34781?

CVE-2021-34781 is a vulnerability with a CVSS score of 8.6 (HIGH). 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 o...

How severe is CVE-2021-34781?

CVE-2021-34781 has been rated HIGH with a CVSS base score of 8.6/10. Review the CVSS metrics above for detailed severity breakdown.

Is there a patch for CVE-2021-34781?

Check the references section above for vendor advisories and patch information. Affected products include: Cisco Firepower Management Center Virtual Appliance, Cisco Firepower Threat Defense, Cisco Sourcefire Defense Center.