CVE-2021-34781

Summary

CVECVE-2021-34781
StatePUBLIC
Assigner[email protected]
Source PriorityCVE Program / NVD first with legacy fallback
Published2021-10-27 19:15:00 UTC
Updated2023-11-07 03:36:00 UTC
DescriptionA 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.

Risk And Classification

Problem Types: CWE-755

NVD Known Affected Configurations (CPE 2.3)

TypeVendorProductVersionUpdateEditionLanguage
Application Cisco Firepower Management Center Virtual Appliance 6.3.0 All All All
Application Cisco Firepower Management Center Virtual Appliance 6.4.0 All All All
Application Cisco Firepower Management Center Virtual Appliance 6.4.0.13 All All All
Application Cisco Firepower Management Center Virtual Appliance 6.5.0 All All All
Application Cisco Firepower Management Center Virtual Appliance 6.6.0 All All All
Application Cisco Firepower Management Center Virtual Appliance 6.7.0.3 All All All
Application Cisco Firepower Management Center Virtual Appliance 6.7.1 All All All
Application Cisco Firepower Management Center Virtual Appliance 7.0.0 All All All
Application Cisco Firepower Threat Defense All All All All
Application Cisco Sourcefire Defense Center 6.3.0 All All All
Application Cisco Sourcefire Defense Center 6.4.0 All All All
Application Cisco Sourcefire Defense Center 6.4.0.13 All All All
Application Cisco Sourcefire Defense Center 6.5.0 All All All
Application Cisco Sourcefire Defense Center 6.6.0 All All All
Application Cisco Sourcefire Defense Center 6.7.0.3 All All All
Application Cisco Sourcefire Defense Center 6.7.1 All All All
Application Cisco Sourcefire Defense Center 7.0.0 All All All

References

ReferenceSourceLinkTags
Cisco Firepower Threat Defense Software SSH Connections Denial of Service Vulnerability CISCO tools.cisco.com
CVE Program record CVE.ORG www.cve.org canonical
NVD vulnerability detail NVD nvd.nist.gov canonical, analysis
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