Vulnerability intelligence
CVE-2026-20303 and is rated Critical severity with a CVSS score of 9.9. It is not in the current CISA KEV record we collected. That does not prove exploitation has not occurred.
To assist customers in patching and streamline the disclosure process, Cisco has grouped these issues by their underlying vulnerability class - Common Weakness Enumeration (CWE) - and assigned a single Common Vulnerabilities and Exposures identifier (CVE ID) to each CWE grouping.
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 software hardening releases that address multiple internally discovered vulnerabilities.
The vulnerabilities tracked by CVE-2026-20303 are related to improper input validation issues that are grouped under the Common Weakness Enumeration (CWE) CWE-20.
Source: NVD