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Vulnerability Intelligence

CVE-2026-20021

Medium 4.3

Published
Last modified
NVD status
Analyzed

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 authenticated, adjacent attacker to exhaust memory on an affected device, resulting in a denial of service (DoS) condition. This vulnerability is due to improperly validating input by the OSPF protocol when parsing packets. An attacker could exploit this vulnerability by by sending crafted OSPF packets to an affected device. A successful exploit could allow the attacker to exhaust memory on the affected device, resulting in a DoS condition.

Affected products

cisco: adaptive security appliance software; cisco: secure firewall threat defense

References1

Metrics

CVSS 3.1
4.3 MEDIUM Score source: CNA CVSS:3.1/AV:A/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:L
EPSS — exploit probability
0% percentile: 13 · as of 12 November 2026
CWE
CWE-401

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