CVE-2026-20023
Cisco Secure Firewall ASA and FTD Software OSPF Memory Corruption Denial of Service
Record summary
CVE-2026-20023 has a selected CVSS score of 6.1 (medium).
Description
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.
Exploitation context
CISA SSVC decision
CISA Coordinator · SSVC 2.0.3 · Evaluated Mar 4, 2026 · Source: CVE List
Affected products and versions
2| Product | Source | Version range | Status |
|---|---|---|---|
Cisco Secure Firewall Adaptive Security Appliance (ASA) SoftwareBrowse Cisco / Cisco Secure Firewall Adaptive Security Appliance (ASA) Software | CVE List | 9.12.1 | affected |
| 9.12.1.2 | affected | ||
| 9.12.1.3 | affected | ||
| 9.12.2 | affected | ||
| 9.12.2.4 | affected | ||
| 9.12.2.5 | affected | ||
| 9.12.2.9 | affected | ||
| 9.12.3 | affected | ||
| 9.12.3.2 | affected | ||
| 9.12.3.7 | affected | ||
| 9.12.4 | affected | ||
| 9.12.3.12 | affected | ||
| Showing 12 of 159 version ranges | |||
Cisco Secure Firewall Threat Defense (FTD) SoftwareBrowse Cisco / Cisco Secure Firewall Threat Defense (FTD) Software | CVE List | 6.4.0 | affected |
| 6.4.0.1 | affected | ||
| 6.4.0.3 | affected | ||
| 6.4.0.2 | affected | ||
| 6.4.0.4 | affected | ||
| 6.4.0.5 | affected | ||
| 6.4.0.6 | affected | ||
| 6.4.0.7 | affected | ||
| 6.4.0.8 | affected | ||
| 6.4.0.9 | affected | ||
| 6.4.0.10 | affected | ||
| 6.4.0.11 | affected | ||
| Showing 12 of 75 version ranges | |||