CVE-2026-20304: Access Control Flaw (CVSS 9.9)

Description

As part of Cisco's ongoing commitment to proactive security and product quality, the Cisco Catalyst SD-WAN engineering team has conducted a comprehensive internal security review. This review resulted in a software hardening release that address multiple internally discovered vulnerabilities. The vulnerabilities tracked by CVE-2026-20304 are related to improper access control issues that are grouped under the Common Weakness Enumeration (CWE) CWE-284.

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CVSS v3.1 Score

9.9

CRITICAL

CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:C/C:H/I:H/A:H

Weakness Type (CWE)

CWE-284 CWE-284

References

Other References

https://sec.cloudapps.cisco.com/security/center/content/CiscoSecurityAdvisory/cisco-sa-hardening-sdwan-faLcR3K

Frequently Asked Questions

What is CVE-2026-20304? +

As part of Cisco's ongoing commitment to proactive security and product quality, the Cisco Catalyst SD-WAN engineering team has conducted a comprehensive internal security review. This review resulted in a software hardening release that address multiple internally discovered vulnerabilities. The vulnerabilities tracked by CVE-2026-20304 are related to improper access control issues that are grouped under the Common Weakness Enumeration (CWE) CWE-284. It has a CVSS v3.1 base score of 9.9 (CRITICAL).

How severe is CVE-2026-20304? +

CVE-2026-20304 has a CVSS v3.1 score of 9.9 out of 10, rated CRITICAL. This is a critical vulnerability that should be patched immediately.

How do I check if I'm vulnerable to CVE-2026-20304? +

You can use Secably's free Website Scanner to check your website for known vulnerabilities. For infrastructure scanning, use the Port Scanner to identify exposed services that may be affected. Check the vendor advisories linked above for specific patch and version information.

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