🔐 CVE Alert

CVE-2026-20021

MEDIUM 4.3
CVSS Score
4.3
EPSS Score
0.0%
EPSS Percentile
0th

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.

CWE CWE-401
Vendor cisco
Product cisco secure firewall adaptive security appliance (asa) software
Ecosystems
Industries
NetworkingTelecommunications
Published Mar 4, 2026
Last Updated Mar 4, 2026
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CVSS v3 Breakdown

CVSS:3.1/AV:A/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:L
Attack Vector
Adjacent
Attack Complexity
Low
Privileges Required
None
User Interaction
None
Scope
Unchanged
Confidentiality
None
Integrity
None
Availability
Low

Affected Versions

Cisco / Cisco Secure Firewall Adaptive Security Appliance (ASA) Software
9.12.1 9.12.1.2 9.12.1.3 9.12.2 9.12.2.4 9.12.2.5 9.12.2.9 9.12.3 9.12.3.2 9.12.3.7 9.12.4 9.12.3.12 9.12.3.9 9.12.2.1 9.12.4.2 9.12.4.4 9.12.4.7 9.12.4.10 9.12.4.13 9.12.4.8 9.12.4.18 9.12.4.24 9.12.4.26 9.12.4.29 9.12.4.30 9.12.4.35 9.12.4.37 9.12.4.38 9.12.4.39 9.12.4.40 9.12.4.41 9.12.4.47 9.12.4.48 9.12.4.50 9.12.4.52 9.12.4.54 9.12.4.55 9.12.4.56 9.12.4.58 9.12.4.62 9.12.4.65 9.12.4.67 9.16.1 9.16.1.28 9.16.2 9.16.2.3 9.16.2.7 9.16.2.11 9.16.2.13 9.16.2.14 9.16.3 9.16.3.3 9.16.3.14 9.16.3.15 9.16.3.19 9.16.3.23 9.16.4 9.16.4.9 9.16.4.14 9.16.4.19 9.16.4.27 9.16.4.38 9.16.4.39 9.16.4.42 9.16.4.48 9.16.4.55 9.16.4.57 9.16.4.61 9.16.4.62 9.16.4.67 9.16.4.70 9.16.4.71 9.16.4.76 9.16.4.82 9.16.4.84 9.16.4.85 9.17.1 9.17.1.7 9.17.1.9 9.17.1.10 9.17.1.11 9.17.1.13 9.17.1.15 9.17.1.20 9.17.1.30 9.17.1.33 9.17.1.39 9.17.1.45 9.17.1.46 9.18.1 9.18.1.3 9.18.2 9.18.2.5 9.18.2.7 9.18.2.8 9.18.3 9.18.3.39 9.18.3.46 9.18.3.53 9.18.3.55 9.18.3.56 9.18.4 9.18.4.5 9.18.4.8 9.18.4.22 9.18.4.24 9.18.4.29 9.18.4.34 9.18.4.40 9.18.4.47 9.18.4.50 9.18.4.52 9.18.4.53 9.18.4.57 9.18.4.66 9.18.4.67 9.18.4.68 9.19.1 9.19.1.5 9.19.1.9 9.19.1.12 9.19.1.18 9.19.1.22 9.19.1.24 9.19.1.27 9.19.1.28 9.19.1.31 9.19.1.37 9.19.1.38 9.19.1.42 9.20.1 9.20.1.5 9.20.2 9.20.2.10 9.20.2.21 9.20.2.22 9.20.3 9.20.3.4 9.20.3.7 9.20.3.9 9.20.3.10 9.20.3.13 9.20.3.16 9.20.3.20 9.20.4 9.20.4.7 9.20.4.10 9.20.4.14 9.22.1.1 9.22.1.3 9.22.1.2 9.22.1.6 9.22.2 9.22.2.4 9.22.2.9 9.22.2.13 9.22.2.14 9.23.1 9.23.1.3 9.23.1.7 9.23.1.13 9.23.1.19 9.23.1.22
Cisco / Cisco Secure Firewall Threat Defense (FTD) Software
6.4.0 6.4.0.1 6.4.0.3 6.4.0.2 6.4.0.4 6.4.0.5 6.4.0.6 6.4.0.7 6.4.0.8 6.4.0.9 6.4.0.10 6.4.0.11 6.4.0.12 6.4.0.13 6.4.0.14 6.4.0.15 6.4.0.16 6.4.0.17 6.4.0.18 7.0.0 7.0.0.1 7.0.1 7.0.1.1 7.0.2 7.0.2.1 7.0.3 7.0.4 7.0.5 7.0.6 7.0.6.1 7.0.6.2 7.0.6.3 7.0.7 7.0.8 7.0.8.1 7.1.0 7.1.0.1 7.1.0.2 7.1.0.3 7.2.0 7.2.0.1 7.2.1 7.2.2 7.2.3 7.2.4 7.2.4.1 7.2.5 7.2.5.1 7.2.6 7.2.7 7.2.5.2 7.2.8 7.2.8.1 7.2.9 7.2.10 7.2.10.2 7.3.0 7.3.1 7.3.1.1 7.3.1.2 7.4.0 7.4.1 7.4.1.1 7.4.2 7.4.2.1 7.4.2.2 7.4.2.3 7.4.2.4 7.4.3 7.6.0 7.6.1 7.6.2 7.6.2.1 7.7.0 7.7.10 7.7.10.1

References

NVD ↗ CVE.org ↗ EPSS Data ↗
sec.cloudapps.cisco.com: https://sec.cloudapps.cisco.com/security/center/content/CiscoSecurityAdvisory/cisco-sa-asaftd-ospf-ZH8PhbSW