Product:
Cisco Secure Firewall
Summary
A vulnerability in the OSPF protocol of Cisco Secure Firewall Adaptive Security Appliance Software and Cisco Secure Firewall Threat Defense Software could allow an authenticated, adjacent attacker to exhaust memory on an affected device, resulting in a denial of service condition. This vulnerability is due to improperly validating input by the OSPF protocol when parsing packets. An attacker could exploit this vulnerability by sending crafted OSPF packets to an affected device.
Details
| Severity | Base Score | CVE |
|---|---|---|
| MEDIUM | 4.3 | CVE-2026-20021 |
Exploitation
To exploit this vulnerability, an attacker must be on the adjacent network and send specially crafted OSPF packets to the affected device. If successful, this could lead to memory exhaustion on the device, causing a denial of service condition.
Affected Products
- Cisco Secure Firewall Adaptive Security Appliance Software: Vulnerable to OSPF protocol issues leading to potential DoS.
- Cisco Secure Firewall Threat Defense Software: Also affected by the same OSPF vulnerability, allowing for similar exploitation.
Mitigation
To mitigate this vulnerability, it is recommended to apply the latest security patches provided by Cisco for the affected products. Additionally, monitoring network traffic for unusual OSPF packets can help in identifying potential exploitation attempts.