CVE-2026-20023
Last modified
CVE-2026-20023 is a medium-severity vulnerability rated 6.5/10 on the CVSS scale. 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. EPSS estimates a 0.15% chance of exploitation in the next 30 days.
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.
Metrics
CVSS:3.1/AV:A/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H
Weakness Enumeration
Affected Software
| Vendor | Product | Versions |
|---|---|---|
| Cisco | Secure Firewall Threat Defense | 6.4.0 |
| Cisco | Secure Firewall Threat Defense | 6.4.0.1 |
| Cisco | Secure Firewall Threat Defense | 6.4.0.2 |
| Cisco | Secure Firewall Threat Defense | 6.4.0.3 |
| Cisco | Secure Firewall Threat Defense | 6.4.0.4 |
| Cisco | Secure Firewall Threat Defense | 6.4.0.5 |
| Cisco | Secure Firewall Threat Defense | 6.4.0.6 |
| Cisco | Secure Firewall Threat Defense | 6.4.0.7 |
| Cisco | Secure Firewall Threat Defense | 6.4.0.8 |
| Cisco | Secure Firewall Threat Defense | 6.4.0.9 |
| Cisco | Secure Firewall Threat Defense | 6.4.0.10 |
| Cisco | Secure Firewall Threat Defense | 6.4.0.11 |
| Cisco | Secure Firewall Threat Defense | 6.4.0.12 |
| Cisco | Secure Firewall Threat Defense | 6.4.0.13 |
| Cisco | Secure Firewall Threat Defense | 6.4.0.14 |
| Cisco | Secure Firewall Threat Defense | 6.4.0.15 |
| Cisco | Secure Firewall Threat Defense | 6.4.0.16 |
| Cisco | Secure Firewall Threat Defense | 6.4.0.17 |
| Cisco | Secure Firewall Threat Defense | 6.4.0.18 |
| Cisco | Secure Firewall Threat Defense | 7.0.0 |
| Cisco | Secure Firewall Threat Defense | 7.0.0.1 |
| Cisco | Secure Firewall Threat Defense | 7.0.1 |
| Cisco | Secure Firewall Threat Defense | 7.0.1.1 |
| Cisco | Secure Firewall Threat Defense | 7.0.2 |
| Cisco | Secure Firewall Threat Defense | 7.0.2.1 |
| Cisco | Secure Firewall Threat Defense | 7.0.3 |
| Cisco | Secure Firewall Threat Defense | 7.0.4 |
| Cisco | Secure Firewall Threat Defense | 7.0.5 |
| Cisco | Secure Firewall Threat Defense | 7.0.6 |
| Cisco | Secure Firewall Threat Defense | 7.0.6.1 |
| Cisco | Secure Firewall Threat Defense | 7.0.6.2 |
| Cisco | Secure Firewall Threat Defense | 7.0.6.3 |
| Cisco | Secure Firewall Threat Defense | 7.0.7 |
| Cisco | Secure Firewall Threat Defense | 7.0.8 |
| Cisco | Secure Firewall Threat Defense | 7.0.8.1 |
| Cisco | Secure Firewall Threat Defense | 7.1.0 |
| Cisco | Secure Firewall Threat Defense | 7.1.0.1 |
| Cisco | Secure Firewall Threat Defense | 7.1.0.2 |
| Cisco | Secure Firewall Threat Defense | 7.1.0.3 |
| Cisco | Secure Firewall Threat Defense | 7.2.0 |
| Cisco | Secure Firewall Threat Defense | 7.2.0.1 |
| Cisco | Secure Firewall Threat Defense | 7.2.1 |
| Cisco | Secure Firewall Threat Defense | 7.2.2 |
| Cisco | Secure Firewall Threat Defense | 7.2.3 |
| Cisco | Secure Firewall Threat Defense | 7.2.4 |
| Cisco | Secure Firewall Threat Defense | 7.2.4.1 |
| Cisco | Secure Firewall Threat Defense | 7.2.5 |
| Cisco | Secure Firewall Threat Defense | 7.2.5.1 |
| Cisco | Secure Firewall Threat Defense | 7.2.5.2 |
| Cisco | Secure Firewall Threat Defense | 7.2.6 |
Showing 50 of 234 affected configurations. See NVD for the full list.
References
Timeline
- Published
- Last Modified
- Status
- Analyzed
Frequently Asked Questions
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How Strix Helps
- How Strix found a critical auth bypass in etcdStrix autonomously discovered a critical authentication bypass in etcd, later designated CVE-2026-33413.
- Autonomous PentestingAI agents that find and validate exploitable vulnerabilities like this one across your applications.
- PR ReviewsPentest every pull request so vulnerable code is caught before it ships to production.
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