Vulnerability · CVE-2026-20022
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…
Published Mar 4, 2026 · corrected/updated Aug 11, 2026 · cisco adaptive security appliance software · evidence confidence high
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 when OSPF canonicalization debug is enabled by using the command debug ip ospf canon. This vulnerability is due to insufficient input validation when processing OSPF LSU packets. An attacker could exploit this vulnerability by sending crafted unauthenticated OSPF packets. A successful exploit could allow the attacker to write to memory outside of the packet data, causing the device to reload, resulting in a DoS condition.
Grounded briefings
Catalog interpretations for three audiences. Each brief cites ingested metadata and the original advisories below. They are not independent research and they do not invent exploit steps.
Executive
CVE-2026-20022 is a medium public vulnerability record for cisco adaptive security appliance software. It is not currently listed in the CISA Known Exploited catalog. Check the linked vendor or CERT advisories for patch status. This summary is a catalog interpretation of the ingested metadata and cites the original advisories below.
System administrator
Identify whether cisco adaptive security appliance software is in your estate, then compare installed versions with the affected ranges. Affected packages or ranges on record: cisco/adaptive security appliance software (9.12.1); cisco/adaptive security appliance software (9.12.1.2); cisco/adaptive security appliance software (9.12.1.3); cisco/adaptive security appliance software (9.12.2). Check the linked vendor or CERT advisories for patch status. Prefer the vendor or distribution advisory linked in Sources before changing production systems. This is a catalog interpretation, not a runbook.
Security analyst
Signals on file: CVSS 6.5, EPSS 0.2%. It is not currently listed in the CISA Known Exploited catalog. Weakness classes: CWE-823. Sources contributing to this record: cve_org, epss, nvd. Public exploit references, when present, are outbound links only and are not proof of active exploitation. This is a catalog interpretation of stored metadata.
Exploitation and remediation
Exploitation evidence
Not listed as known exploited in CISA KEV. Not in CISA KEV or VulnCheck KEV.
Patch and remediation
No required-action text is stored yet. Use the vendor or CERT links in Sources for patch availability.
Safe detection guidance
Compare installed versions with the affected ranges below and verify the advisory from the original publisher. This site stores metadata and outbound links only; it does not ship exploit code or proof-of-concept payloads.
Technology hubs
Code
The project this record applies to. Exploit listings stay in References.
No public source repository is identified for this product.
Timeline
Detection, updates, and resolution for this record.
Mar 4, 2026 · NIST NVD
Detected
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 when OSPF canonicalization debug is enabled by using the command debug ip ospf canon. This vulnerability is due to insufficient input validation when processing OSP
Aug 11, 2026 · NIST NVD
Updated
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 when OSPF canonicalization debug is enabled by using the command debug ip ospf canon. This vulnerability is due to insufficient input validation when processing OSP
Affected
- cpe cisco/adaptive security appliance software9.12.1
- cpe cisco/adaptive security appliance software9.12.1.2
- cpe cisco/adaptive security appliance software9.12.1.3
- cpe cisco/adaptive security appliance software9.12.2
- cpe cisco/adaptive security appliance software9.12.2.1
- cpe cisco/adaptive security appliance software9.12.2.4
- cpe cisco/adaptive security appliance software9.12.2.5
- cpe cisco/adaptive security appliance software9.12.2.9
- cpe cisco/secure firewall threat defense6.4.0
Sources
- CVE.orgVulnerability recordCVE-2026-20022
Official CVE identifier
cve.org - FIRST EPSSExploitation probabilityCVE-2026-20022
30-day exploitation probability 0.2%
first.org - NIST NVDVulnerability recordCVE-2026-20022
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 when OSPF canonicalization debug is enabled
nvd.nist.gov