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CVE-2026-20303

Cisco Catalyst SD-WAN Security Hardening Release - Input Validation Vulnerabilities

Published: Aug 5, 2026Updated: Aug 6, 2026 Sources: CVE List NVDCWE-20
9.9CRITICAL
NVD MITRE
EPSS Score
0.3%
Top 78.7%
CISA KEV
Not in KEV
Exploits
0 Known
Remediation
No Fix Available
Self-Check
OpenVAS

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.

No summary for this CVE yet.

CVSS Vector Breakdown

AV:NAC:LPR:LUI:NS:CC:HI:HA:H
Exploitability
AV:NAttack Vector
Network
AC:LAttack Complexity
Low
PR:LPrivileges Required
Low
UI:NUser Interaction
None
Scope
S:CScope
Changed
Impact
C:HConfidentiality
High
I:HIntegrity
High
A:HAvailability
High
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Weaknesses

CWE-20

Affected Products

Cisco
commercial·USaka cisco systems inc., cisco systems
Cisco Catalyst SD-WAN Controller
Networking Infrastructure
Cisco Catalyst SD-WAN Manager
Networking Infrastructure

Exploitability

0 exploit sources identified

Exploit details including PoC links, Metasploit modules, and scanner templates are available after registration.

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Attack Graph

Products CVE Techniques Tactics

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MITRE ATT&CK

1 technique
Initial Access
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References

https://sec.cloudapps.cisco.com/security/center/content/CiscoSecurityAdvisory/cisco-sa-hardening-sdwan-faLcR3K
sec.cloudapps.cisco.com
News mentions
2

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