Cisco Security Advisoriescisco-sa-hardening-sdwan-faLcR3K

Cisco Catalyst SD-WAN Software Security Hardening Release: August 2026

As part of Cisco's ongoing commitment to proactive security and product quality, the Cisco Catalyst SD-WAN Software engineering team has conducted a comprehensive internal security review. This review resulted in software hardening releases that address multiple internally discovered vulnerabilities. These vulnerabilities were found during internal testing and are not known to be actively exploited. 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. Cisco has released software updates that address these vulnerabilities. There are no workarounds that address these vulnerabilities. This advisory is available at the following link:https://sec.cloudapps.cisco.com/security/center/content/CiscoSecurityAdvisory/cisco-sa-hardening-sdwan-faLcR3K Security Impact Rating: Critical CVE: CVE-2026-20303,CVE-2026-20304,CVE-2026-20310,CVE-2026-20312,CVE-2026-20313

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CriticalCVSS not listedCritical severity

Scope

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What the vendor recommends

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.

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Timeline

When this advisory changed

Aug 5, 2026 at 4:00 PM UTC
Published by Cisco
The publication date reported by the vendor.
Aug 20, 2026 at 2:20 AM UTC
Added to SecurityAlert
We collected the advisory from the official source.
Aug 26, 2026 at 3:50 PM UTC
Confirmed at the source
Our collector saw this advisory during a later source check.

Vulnerabilities

CVEs named in this advisory

CVE-2026-20303View CVSS, KEV, EPSS, and threat context CVE-2026-20304View CVSS, KEV, EPSS, and threat context CVE-2026-20310View CVSS, KEV, EPSS, and threat context CVE-2026-20312View CVSS, KEV, EPSS, and threat context CVE-2026-20313View CVSS, KEV, EPSS, and threat context

Source

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Vendor: Cisco
Advisory ID: cisco-sa-hardening-sdwan-faLcR3K
Last source check: Sep 13, 2026 at 4:50 AM UTC

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