CVE-2026-20303: Improper Input Validation in Cisco Cisco Catalyst SD-WAN Controller
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.
AI Analysis
Technical Summary
This vulnerability, tracked as CVE-2026-20303, involves improper input validation in Cisco Catalyst SD-WAN Controller software. It was discovered internally by Cisco during a comprehensive security review and is categorized under CWE-20. The CVSS v3.1 base score is 9.9, reflecting network attack vector, low attack complexity, required privileges, no user interaction, and complete impact on confidentiality, integrity, and availability. The affected versions include numerous specific releases of Cisco Catalyst SD-WAN Controller as enumerated. No vendor advisory or patch information is currently available to confirm remediation status.
Potential Impact
If exploited, this vulnerability could allow an attacker with network access and low complexity to compromise the confidentiality, integrity, and availability of the affected Cisco Catalyst SD-WAN Controller systems. The critical CVSS score indicates a severe impact, potentially enabling full system compromise or disruption.
Mitigation Recommendations
Patch status is not yet confirmed — check the vendor advisory for current remediation guidance. Cisco has released software hardening updates addressing multiple vulnerabilities discovered internally, but no specific patch or mitigation details for CVE-2026-20303 have been provided. Users should monitor Cisco's official advisories for updates and apply patches promptly once available.
CVE-2026-20303: Improper Input Validation in Cisco Cisco Catalyst SD-WAN Controller
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 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.
CVSS v3.1
Score 9.9critical
Affected software
AI-Powered Analysis
Machine-generated threat intelligence
Technical Analysis
This vulnerability, tracked as CVE-2026-20303, involves improper input validation in Cisco Catalyst SD-WAN Controller software. It was discovered internally by Cisco during a comprehensive security review and is categorized under CWE-20. The CVSS v3.1 base score is 9.9, reflecting network attack vector, low attack complexity, required privileges, no user interaction, and complete impact on confidentiality, integrity, and availability. The affected versions include numerous specific releases of Cisco Catalyst SD-WAN Controller as enumerated. No vendor advisory or patch information is currently available to confirm remediation status.
Potential Impact
If exploited, this vulnerability could allow an attacker with network access and low complexity to compromise the confidentiality, integrity, and availability of the affected Cisco Catalyst SD-WAN Controller systems. The critical CVSS score indicates a severe impact, potentially enabling full system compromise or disruption.
Mitigation Recommendations
Patch status is not yet confirmed — check the vendor advisory for current remediation guidance. Cisco has released software hardening updates addressing multiple vulnerabilities discovered internally, but no specific patch or mitigation details for CVE-2026-20303 have been provided. Users should monitor Cisco's official advisories for updates and apply patches promptly once available.
Technical Details
- Data Version
- 5.2
- Assigner Short Name
- cisco
- Date Reserved
- 2025-10-08T11:59:15.408Z
- Cvss Version
- 3.1
- State
- PUBLISHED
- Remediation Level
- null
Threat ID: 6a736b62bf8831d5392da512
Added to database: 08/05/2026, 16:57:06 UTC
Last enriched: 08/05/2026, 17:15:07 UTC
Last updated: 08/05/2026, 17:57:23 UTC
Views: 3
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