Cisco Secure Firewall Adaptive Security Appliance and Secure Firewall Threat Defense Software for Firepower 3100 and 4200 Series DTLS Denial of Service Vulnerability

MITRE NVD CVE.ORG JSON API

Summary

CVECVE-2026-20250
StatePUBLISHED
Assignercisco
Source PriorityCVE Program / NVD first with legacy fallback
Published2026-09-16 21:17:08 UTC
Updated2026-09-18 13:28:28 UTC
DescriptionA vulnerability in Datagram TLS (DTLS) message handling of Cisco Secure Firewall Adaptive Security Appliance (ASA) Software and Cisco Secure Firewall Threat Defense (FTD) Software for Cisco Secure Firewall 3100 Series and 4200 Series devices could allow an unauthenticated, remote attacker to cause a denial of service (DoS) condition on an affected device. This vulnerability is due to improper resource management when processing certain DTLS messages. An attacker could exploit this vulnerability by sending a crafted stream of DTLS traffic to an affected device. A successful exploit could allow the attacker to cause the device to reload, resulting in a DoS condition.

Risk And Classification

Primary CVSS: v3.1 8.6 HIGH from [email protected]

CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:C/C:N/I:N/A:H

EPSS: 0.005490000 probability, percentile 0.448010000 (date 2026-09-20)

Problem Types: CWE-772 | CWE-772 Missing Release of Resource after Effective Lifetime

VersionSourceTypeScoreSeverityVector
3.1[email protected]Secondary8.6HIGHCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:C/C:N/I:N/A:H
3.1CNACVSSV3_18.6HIGHCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:C/C:N/I:N/A:H

CVSS v3.1 Breakdown

Attack Vector
Network
Attack Complexity
Low
Privileges Required
None
User Interaction
None
Scope
Changed
Confidentiality
None
Integrity
None
Availability
High

CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:C/C:N/I:N/A:H

Vendor Declared Affected Products

SourceVendorProductVersionPlatforms
CNA Cisco Cisco Secure Firewall Adaptive Security Appliance ASA Software affected 9.23.1 Not specified
CNA Cisco Cisco Secure Firewall Adaptive Security Appliance ASA Software affected 9.22.1.1 Not specified
CNA Cisco Cisco Secure Firewall Adaptive Security Appliance ASA Software affected 9.22.1.3 Not specified
CNA Cisco Cisco Secure Firewall Adaptive Security Appliance ASA Software affected 9.22.1.6 Not specified
CNA Cisco Cisco Secure Firewall Adaptive Security Appliance ASA Software affected 9.22.2 Not specified
CNA Cisco Cisco Secure Firewall Adaptive Security Appliance ASA Software affected 9.23.1.3 Not specified
CNA Cisco Cisco Secure Firewall Adaptive Security Appliance ASA Software affected 9.22.2.4 Not specified
CNA Cisco Cisco Secure Firewall Adaptive Security Appliance ASA Software affected 9.23.1.7 Not specified
CNA Cisco Cisco Secure Firewall Adaptive Security Appliance ASA Software affected 9.22.2.9 Not specified
CNA Cisco Cisco Secure Firewall Adaptive Security Appliance ASA Software affected 9.23.1.13 Not specified
CNA Cisco Cisco Secure Firewall Adaptive Security Appliance ASA Software affected 9.22.2.13 Not specified
CNA Cisco Cisco Secure Firewall Adaptive Security Appliance ASA Software affected 9.23.1.19 Not specified
CNA Cisco Cisco Secure Firewall Adaptive Security Appliance ASA Software affected 9.22.2.14 Not specified
CNA Cisco Cisco Secure Firewall Adaptive Security Appliance ASA Software affected 9.24.1 Not specified
CNA Cisco Cisco Secure Firewall Adaptive Security Appliance ASA Software affected 9.23.1.22 Not specified
CNA Cisco Cisco Secure Firewall Adaptive Security Appliance ASA Software affected 9.22.2.20 Not specified
CNA Cisco Cisco Secure Firewall Adaptive Security Appliance ASA Software affected 9.23.1.26 Not specified
CNA Cisco Cisco Secure Firewall Threat Defense FTD Software affected 7.6.0 Not specified
CNA Cisco Cisco Secure Firewall Threat Defense FTD Software affected 7.7.0 Not specified
CNA Cisco Cisco Secure Firewall Threat Defense FTD Software affected 7.6.1 Not specified
CNA Cisco Cisco Secure Firewall Threat Defense FTD Software affected 7.6.2 Not specified
CNA Cisco Cisco Secure Firewall Threat Defense FTD Software affected 7.7.10 Not specified
CNA Cisco Cisco Secure Firewall Threat Defense FTD Software affected 7.7.11 Not specified
CNA Cisco Cisco Secure Firewall Threat Defense FTD Software affected 7.6.2.1 Not specified
CNA Cisco Cisco Secure Firewall Threat Defense FTD Software affected 7.7.10.1 Not specified
CNA Cisco Cisco Secure Firewall Threat Defense FTD Software affected 7.6.4 Not specified
CNA Cisco Cisco Secure Firewall Threat Defense FTD Software affected 10.0.0 Not specified

References

ReferenceSourceLinkTags
sec.cloudapps.cisco.com/security/center/content/CiscoSecurityAdvisory/cisco-sa-asaftd... [email protected] sec.cloudapps.cisco.com
CVE Program record CVE.ORG www.cve.org canonical
NVD vulnerability detail NVD nvd.nist.gov canonical, analysis

Additional Advisory Data

Exploits

CNA: The Cisco Product Security Incident Response Team (PSIRT) is not aware of any public announcements or malicious use of the vulnerability that is described in this advisory.

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