PT-2026-23038 · Cisco · Cisco Secure Firewall Asa+1

Jason Crowder · Published 2026-03-04 · Updated 2026-03-05 · CVE-2026-20021

Positive Technologies (AI Summary)

CVSS v3.1

4.3

Medium

Base vector

AV:A/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:L

Name of the Vulnerable Software and Affected Versions Cisco Secure Firewall Adaptive Security Appliance (ASA) Software and Cisco Secure Firewall Threat Defense (FTD) Software (affected versions not specified)

Description A flaw exists in the OSPF protocol implementation of the software that could allow a nearby, authorized attacker to deplete device memory, leading to a denial of service. This is caused by improper input validation when processing OSPF packets. An attacker can exploit this by sending specially crafted OSPF packets to the device. A successful exploit could exhaust memory, resulting in a denial of service condition.

Recommendations At the moment, there is no information about a newer version that contains a fix for this vulnerability.

DoS

Memory Leak

Weakness Enumeration

CWE-401

Related Identifiers

CVE-2026-20021

Affected Products

Cisco Secure Firewall Asa

Cisco Secure Firewall Ftd

References · 5

• https://nvd.nist.gov/vuln/detail/CVE-2026-20021 · Security Note
• https://sec.cloudapps.cisco.com/security/center/content/CiscoSecurityAdvisory/cisco-sa-asaftd-ospf-ZH8PhbSW · Vendor Advisory
• https://twitter.com/CVEnew/status/2029272776440262695 · Twitter Post
• https://t.me/CVEtracker/46347 · Telegram Post
• https://twitter.com/VulmonFeeds/status/2029413167944646970 · Twitter Post