A vulnerability in the OSPF protocol of Cisco Secure Firewall Adaptive Security Appliance (ASA) Software and Cisco Secure Firewall Threat D…

published 2026-03-04 8 mo ago modified 2026-08-11 2 mo ago also EUVD-2026-9480

cvss: 6.1; version 3.1, CNA
cisa kev: Not listed; not in CISA's catalog
epss: 0.2%; EPSS 0.2% chance of exploitation in 30 days, percentile 6%
public exploits: 0; none known

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 unauthenticated, adjacent attacker to corrupt memory on an affected device, resulting in a denial of service (DoS) condition. This vulnerability is due to memory corruption when parsing OSPF protocol packets. An attacker could exploit this vulnerability by sending crafted OSPF packets to an affected device. A successful exploit could allow the attacker to cause memory corruption causing the affected device to reboot, resulting in a DoS condition.

CISA SSVC

Exploitation: none
Automatable: no
Technical impact: partial
Assessed: 8 mo ago (2026-03-04)

Exploit prediction

0.17% chance of exploitation in the next 30 days, higher than 6% of all scored CVEs (FIRST EPSS, 2026-11-08).

CVSS scores

assigned by	version	score	vector
CNA	3.1	6.1	CVSS:3.1/AV:A/AC:H/PR:N/UI:N/S:C/C:N/I:N/A:H
NVD	3.1	6.5	CVSS:3.1/AV:A/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H

Affected products

Cisco Cisco Secure Firewall Adaptive Security Appliance (ASA) Software
Cisco Cisco Secure Firewall Threat Defense (FTD) Software

Classification

Weakness

CWE-787 Out-of-bounds Write

References

sec.cloudapps.cisco.com /security/center/content/CiscoSecurityAdvisory/cisco-sa-asaftd-ospf-ZH8PhbSW
vendor-advisory

Sources

CVE List CVE-2026-20023
NVD CVE-2026-20023

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Summary