CVE-2026-20021
published 2026-03-04CVE-2026-20021: A vulnerability in the OSPF protocol of Cisco Secure Firewall Adaptive Security Appliance (ASA) Software and Cisco Secure Firewall Threat Defense (FTD)…
PriorityP421medium4.3CVSS 3.1
AVAACLPRNUINSUCNINAL
EPSS
0.21%
11.6th percentile
A vulnerability in the OSPF protocol of Cisco Secure Firewall Adaptive Security Appliance (ASA) Software and Cisco Secure Firewall Threat Defense (FTD) Software could allow an authenticated, adjacent attacker to exhaust memory on an affected device, resulting in a denial of service (DoS) condition.
This vulnerability is due to improperly validating input by the OSPF protocol when parsing packets. An attacker could exploit this vulnerability by by sending crafted OSPF packets to an affected device. A successful exploit could allow the attacker to exhaust memory on the affected device, resulting in a DoS condition.
Affected
324 ranges· showing 25
| Vendor | Product | Version range | Fixed in |
|---|---|---|---|
| cisco | adaptive_security_appliance_software | 9.12.1 – 9.12.4.67 | — |
| cisco | adaptive_security_appliance_software | 9.16.1 – 9.16.4.85 | — |
| cisco | adaptive_security_appliance_software | 9.17.1 – 9.17.1.46 | — |
| cisco | adaptive_security_appliance_software | 9.18.1 – 9.18.4.68 | — |
| cisco | adaptive_security_appliance_software | 9.19.1 – 9.19.1.42 | — |
| cisco | adaptive_security_appliance_software | 9.20.1 – 9.20.4.14 | — |
| cisco | adaptive_security_appliance_software | 9.22.1.1 – 9.22.2.14 | — |
| cisco | adaptive_security_appliance_software | 9.23.1 – 9.23.1.22 | — |
| cisco | cisco_secure_firewall_adaptive_security_appliance_software | — | — |
| cisco | cisco_secure_firewall_adaptive_security_appliance_software | — | — |
| cisco | cisco_secure_firewall_adaptive_security_appliance_software | — | — |
| cisco | cisco_secure_firewall_adaptive_security_appliance_software | — | — |
| cisco | cisco_secure_firewall_adaptive_security_appliance_software | — | — |
| cisco | cisco_secure_firewall_adaptive_security_appliance_software | — | — |
| cisco | cisco_secure_firewall_adaptive_security_appliance_software | — | — |
| cisco | cisco_secure_firewall_adaptive_security_appliance_software | — | — |
| cisco | cisco_secure_firewall_adaptive_security_appliance_software | — | — |
| cisco | cisco_secure_firewall_adaptive_security_appliance_software | — | — |
| cisco | cisco_secure_firewall_adaptive_security_appliance_software | — | — |
| cisco | cisco_secure_firewall_adaptive_security_appliance_software | — | — |
| cisco | cisco_secure_firewall_adaptive_security_appliance_software | — | — |
| cisco | cisco_secure_firewall_adaptive_security_appliance_software | — | — |
| cisco | cisco_secure_firewall_adaptive_security_appliance_software | — | — |
| cisco | cisco_secure_firewall_adaptive_security_appliance_software | — | — |
| cisco | cisco_secure_firewall_adaptive_security_appliance_software | — | — |
CVSS provenance
nvdv3.14.3MEDIUMCVSS:3.1/AV:A/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:L
vendor_cisco6.8MEDIUM
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Cisco
Cisco Secure Firewall Adaptive Security Appliance and Secure Firewall Threat Defense Software OSPF Protocol Vulnerabilities
vendor_cisco·2026-03-04·CVSS 6.8
CVE-2026-20020 [MEDIUM] CWE-119 Cisco Secure Firewall Adaptive Security Appliance and Secure Firewall Threat Defense Software OSPF Protocol Vulnerabilities
Cisco Secure Firewall Adaptive Security Appliance and Secure Firewall Threat Defense Software OSPF Protocol Vulnerabilities
Multiple vulnerabilities in the OSPF feature of Cisco Secure Firewall Adaptive Security Appliance (ASA) Software and Cisco Secure Firewall Threat Defense (FTD) Software could allow an adjacent attacker to cause the device to reload unexpectedly, resulting in a denial of service (DoS) condition.
For more information about these vulnerabilities, see the Details section of this advisory.
Cisco has released software updates that address these vulnerabilities. There are no workarounds that address these vulnerabilities.
This advisory is available at the following link:https://sec.cloudapps.cisco.com/security/center/content/CiscoSecurityAdvisory/cisco-sa-asaftd-ospf-ZH8Phb
Cisco
Cisco Secure Firewall Adaptive Security Appliance and Secure Firewall Threat Defense Software OSPF Protocol Vulnerabilities
vendor_cisco·CVSS 3.1
CVE-2026-20021 Cisco Secure Firewall Adaptive Security Appliance and Secure Firewall Threat Defense Software OSPF Protocol Vulnerabilities
CVE-2026-20021: Cisco Secure Firewall Adaptive Security Appliance and Secure Firewall Threat Defense Software OSPF Protocol Vulnerabilities
Multiple vulnerabilities in the OSPF feature of Cisco Secure Firewall Adaptive Security Appliance (ASA) Software and Cisco Secure Firewall Threat Defense (FTD) Software could allow an adjacent attacker to cause the device to reload unexpectedly, resulting in a denial of service (DoS) condition. For more information about these vulnerabilities, see the
CVSS: 3.1
CWE: CWE-119, CWE-190, CWE-20, CWE-119, CWE-190, CWE-20, CWE-401, CWE-787, CWE-823, CWE-119, CWE-190, CWE-20, CWE-119, CWE-190, CWE-20, CWE-401, CWE-787, CWE-823
Bug IDs: CSCwn69075, CSCwn69076, CSCwn69078, CSCwn69075, CSCwn69076
GHSA
GHSA-qjf3-5p7q-6r9m: A vulnerability in the OSPF protocol of Cisco Secure Firewall Adaptive Security Appliance (ASA) Software and Cisco Secure Firewall Threat Defense (FTD
ghsa_unreviewed·2026-03-04
CVE-2026-20021 [MEDIUM] CWE-401 GHSA-qjf3-5p7q-6r9m: A vulnerability in the OSPF protocol of Cisco Secure Firewall Adaptive Security Appliance (ASA) Software and Cisco Secure Firewall Threat Defense (FTD
A vulnerability in the OSPF protocol of Cisco Secure Firewall Adaptive Security Appliance (ASA) Software and Cisco Secure Firewall Threat Defense (FTD) Software could allow an authenticated, adjacent attacker to exhaust memory on an affected device, resulting in a denial of service (DoS) condition.
This vulnerability is due to improperly validating input by the OSPF protocol when parsing packets. An attacker could exploit this vulnerability by by sending crafted OSPF packets to an affected device. A successful exploit could allow the attacker to exhaust memory on the affected device, resulting in a DoS condition.
No detection rules found.
No public exploits indexed.
No writeups or analysis indexed.
2026-03-04
Published