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CVE-2026-20021

Published: Mar 4, 2026Updated: Apr 16, 2026 Sources: CVE List NVDCWE-401
4.3CVSSMEDIUM

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.

CVSS Vector Breakdown

AV:AAC:LPR:NUI:NS:UC:NI:NA:L
Exploitability
AV:AAttack Vector
Adjacent
AC:LAttack Complexity
Low
PR:NPrivileges Required
None
UI:NUser Interaction
None
Scope
S:UScope
Unchanged
Impact
C:NConfidentiality
None
I:NIntegrity
None
A:LAvailability
Low

Weaknesses

Affected Products

ciscocommercialUSNetworking Infrastructureaka cisco systems, cisco systems inc.

Exploitability

0 exploit sources identified

Exploit details including PoC links, Metasploit modules, and scanner templates are available after registration.

View exploit details
Official Patch Available

References

Timeline

Published
Mar 4, 2026
Last Updated
Apr 16, 2026

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