CVE-2026-20304criticalCWE-284

CVE-2026-20304: critical vulnerability in Cisco Catalyst SD-WAN Controller

Cisco Catalyst SD-WAN Security Hardening Release - Access Control Vulnerabilities

Published · Updated

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E-mail alert when it lands in KEV, gets a public PoC or its score goes up.

28Vexday Risk Score

No sign of exploitation. It has an official Brazilian government alert.

ssvc Trackcvss 9.9epss 0.4%
Official alert in Brazil

Brazil's federal government published an alert, recommendation or bulletin that cites this vulnerability.

Source: CTIR Gov (GSI) and CISC Gov.br, under the CC BY-ND 3.0 license.
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.
CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:C/C:H/I:H/A:H
Affected products
Cisco · Cisco Catalyst SD-WAN ControllerCisco · Cisco Catalyst SD-WAN Manager
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