CVE-2026-20303CWE-20

CVE-2026-20303

Critical · published August 5, 2026

CVSS v3.1
9.9
EPSS
0%
Percentile
41.0
In the wild
Unconfirmed
What it is

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.

The record
Technical detail
CVSS v3.1
9.9 · CRITICAL
Vector
CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:C/C:H/I:H/A:H
CVSS v4.0
Not supplied
EPSS
0.00487 · 41.0th percentile
Weakness
CWE-20 · Improper Input Validation
Published
2026-08-05T21:16Z
References (2)
https://sec.cloudapps.cisco.com/security/center/content/CiscoSecurityAdvisory/cisco-sa-hardening-sdwan-faLcR3K · [email protected]https://www.cve.org/Media/News/item/blog/2026/06/16/Preserving-Vulnerability-Level-Identification · af854a3a-2127-422b-91ae-364da2661108
EPSS history
Timeline
  • 05 AUG 16:29Z
    Cisco Catalyst SD-WAN Security Hardening Release - Input Validation Vulnerabilities
    cvelistv5