CVE-2026-20020
Last modified
CVE-2026-20020 is a medium-severity vulnerability rated 5.7/10 on the CVSS scale. A vulnerability in the OSPF protocol of Cisco Secure Firewall ASA Software and Cisco Secure FTD Software could allow an unauthenticated, adjacent attacker to cause an affected device to reload unexpectedly, resulting in a DoS condition. If OSPF authentication is enabled, the attacker must know the secret key to exploit this vulnerability. This vulnerability is due to insufficient input validation when processing OSPF update packets. EPSS estimates a 0.25% chance of exploitation in the next 30 days.
Description
A vulnerability in the OSPF protocol of Cisco Secure Firewall ASA Software and Cisco Secure FTD Software could allow an unauthenticated, adjacent attacker to cause an affected device to reload unexpectedly, resulting in a DoS condition. If OSPF authentication is enabled, the attacker must know the secret key to exploit this vulnerability. This vulnerability is due to insufficient input validation when processing OSPF update packets. An attacker could exploit this vulnerability by sending crafted OSPF update packets. A successful exploit could allow the attacker to create a buffer overflow, causing the affected device to reload, resulting in a DoS condition.
Metrics
CVSS:3.1/AV:A/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H
Weakness Enumeration
Affected Software
| Vendor | Product | Versions |
|---|---|---|
| Cisco | Adaptive Security Appliance Software | 9.12.1 |
| Cisco | Adaptive Security Appliance Software | 9.12.1.2 |
| Cisco | Adaptive Security Appliance Software | 9.12.1.3 |
| Cisco | Adaptive Security Appliance Software | 9.12.2 |
| Cisco | Adaptive Security Appliance Software | 9.12.2.1 |
| Cisco | Adaptive Security Appliance Software | 9.12.2.4 |
| Cisco | Adaptive Security Appliance Software | 9.12.2.5 |
| Cisco | Adaptive Security Appliance Software | 9.12.2.9 |
| Cisco | Adaptive Security Appliance Software | 9.12.3 |
| Cisco | Adaptive Security Appliance Software | 9.12.3.2 |
| Cisco | Adaptive Security Appliance Software | 9.12.3.7 |
| Cisco | Adaptive Security Appliance Software | 9.12.3.9 |
| Cisco | Adaptive Security Appliance Software | 9.12.3.12 |
| Cisco | Adaptive Security Appliance Software | 9.12.4 |
| Cisco | Adaptive Security Appliance Software | 9.12.4.2 |
| Cisco | Adaptive Security Appliance Software | 9.12.4.4 |
| Cisco | Adaptive Security Appliance Software | 9.12.4.7 |
| Cisco | Adaptive Security Appliance Software | 9.12.4.8 |
| Cisco | Adaptive Security Appliance Software | 9.12.4.10 |
| Cisco | Adaptive Security Appliance Software | 9.12.4.13 |
| Cisco | Adaptive Security Appliance Software | 9.12.4.18 |
| Cisco | Adaptive Security Appliance Software | 9.12.4.24 |
| Cisco | Adaptive Security Appliance Software | 9.12.4.26 |
| Cisco | Adaptive Security Appliance Software | 9.12.4.29 |
| Cisco | Adaptive Security Appliance Software | 9.12.4.30 |
| Cisco | Adaptive Security Appliance Software | 9.12.4.35 |
| Cisco | Adaptive Security Appliance Software | 9.12.4.37 |
| Cisco | Adaptive Security Appliance Software | 9.12.4.38 |
| Cisco | Adaptive Security Appliance Software | 9.12.4.39 |
| Cisco | Adaptive Security Appliance Software | 9.12.4.40 |
| Cisco | Adaptive Security Appliance Software | 9.12.4.41 |
| Cisco | Adaptive Security Appliance Software | 9.12.4.47 |
| Cisco | Adaptive Security Appliance Software | 9.12.4.48 |
| Cisco | Adaptive Security Appliance Software | 9.12.4.50 |
| Cisco | Adaptive Security Appliance Software | 9.12.4.52 |
| Cisco | Adaptive Security Appliance Software | 9.12.4.54 |
| Cisco | Adaptive Security Appliance Software | 9.12.4.55 |
| Cisco | Adaptive Security Appliance Software | 9.12.4.56 |
| Cisco | Adaptive Security Appliance Software | 9.12.4.58 |
| Cisco | Adaptive Security Appliance Software | 9.12.4.62 |
| Cisco | Adaptive Security Appliance Software | 9.12.4.65 |
| Cisco | Adaptive Security Appliance Software | 9.12.4.67 |
| Cisco | Adaptive Security Appliance Software | 9.16.1 |
| Cisco | Adaptive Security Appliance Software | 9.16.1.28 |
| Cisco | Adaptive Security Appliance Software | 9.16.2 |
| Cisco | Adaptive Security Appliance Software | 9.16.2.3 |
| Cisco | Adaptive Security Appliance Software | 9.16.2.7 |
| Cisco | Adaptive Security Appliance Software | 9.16.2.11 |
| Cisco | Adaptive Security Appliance Software | 9.16.2.13 |
| Cisco | Adaptive Security Appliance Software | 9.16.2.14 |
Showing 50 of 221 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.
- AI Penetration TestingHow AI-driven penetration testing continuously covers your attack surface.
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