CVE-2021-34781

Cisco Firepower Threat Defense Software SSH Connections Denial of Service 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.

Categories

8.6
CVSS
Severity: High
CVSS 3.1 •
CVSS 2.0 •
EPSS 0.43%
Vendor Advisory cisco.com
Affected: Cisco Cisco Adaptive Security Appliance (ASA) Software
Published at:
Updated at:

References

Frequently Asked Questions

What is the severity of CVE-2021-34781?
CVE-2021-34781 has been scored as a high severity vulnerability.
How to fix CVE-2021-34781?
To fix CVE-2021-34781, make sure you are using an up-to-date version of the affected component(s) by checking the vendor release notes. As for now, there are no other specific guidelines available.
Is CVE-2021-34781 being actively exploited in the wild?
As for now, there are no information to confirm that CVE-2021-34781 is being actively exploited. According to its EPSS score, there is a ~0% probability that this vulnerability will be exploited by malicious actors in the next 30 days.
What software or system is affected by CVE-2021-34781?
CVE-2021-34781 affects Cisco Cisco Adaptive Security Appliance (ASA) Software.
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