Cisco Security Advisoriescisco-sa-sdwan-webauth-xr8beuuU

Cisco Catalyst SD-WAN Manager API Authentication Bypass Vulnerability

A vulnerability in the API session-based authentication management of Cisco Catalyst SD-WAN Manager could allow an unauthenticated, remote attacker to access an affected system with privileges of the admin user. This vulnerability is due to improper handling of URI encoding in an HTTP request, which allows the request to bypass an authentication rule that is intended to restrict access to a specific API endpoint. An attacker could exploit this vulnerability by sending a crafted HTTP request to the API of the affected system. A successful exploit could allow the attacker to bypass authentication and gain access to the API as the admin user. Cisco has released software updates that address this vulnerability. There are no workarounds that address this vulnerability. This advisory is available at the following link: https://sec.cloudapps.cisco.com/security/center/content/CiscoSecurityAdvisory/cisco-sa-sdwan-webauth-xr8beuuU Security Impact Rating: Critical CVE: CVE-2026-76504

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CriticalCVSS not listedCritical severity

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Sep 30, 2026 at 1:00 PM UTC
Published by Cisco
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Sep 30, 2026 at 1:20 PM UTC
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CVE-2026-76504View CVSS, KEV, EPSS, and threat context

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Vendor: Cisco
Advisory ID: cisco-sa-sdwan-webauth-xr8beuuU
Last source check: Sep 30, 2026 at 3:00 PM UTC

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