CVE-2026-20020 — Improper Input Validation in Cisco Secure Firewall Adaptive Security Appliance Software

CWE-20 — Improper Input ValidationCWE-119 — Improper Restriction of Operations within the Bounds of a Memory BufferCWE-190 — Integer Overflow or WraparoundCWE-401 — Missing Release of Memory after Effective LifetimeCWE-787 — Out-of-bounds WriteCWE-823 — Use of Out-of-range Pointer Offset4 documents4 sources
Severity
6.8MEDIUMNVD
EPSS
0.0%
top 88.79%
CISA KEV
Not in KEV
Exploit
No known exploits
Affected products
2
Cisco Secure Firewall Adaptive Security Appliance SoftwareCisco Secure Firewall Threat Defense Software
Timeline
PublishedMar 4

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…

CVSS vector

CVSS:3.1/AV:A/AC:L/PR:L/UI:N/S:C/C:N/I:N/A:HExploitability: 2.3 | Impact: 4.0

Affected Packages2 packages

🔴Vulnerability Details

2
GHSA
GHSA-9qmm-x6v7-php3: A vulnerability in the OSPF protocol of Cisco Secure Firewall ASA Software and Cisco Secure FTD Software could allow an unauthenticated, adjacent atta↗2026-03-04
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CVEList
CVE-2026-20020: A vulnerability in the OSPF protocol of Cisco Secure Firewall ASA Software and Cisco Secure FTD Software could allow an unauthenticated, adjacent atta↗2026-03-04
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📋Vendor Advisories

1
Cisco
Cisco Secure Firewall Adaptive Security Appliance and Secure Firewall Threat Defense Software OSPF Protocol Vulnerabilities↗2026-03-04
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CVE-2026-20020 — Improper Input Validation in Cisco | cvebase