Disclosure summary
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.
CISA remediation guidance
Apply mitigations in accordance with vendor instructions, ensuring compliance with CISA’s BOD 26-04 Prioritizing Security Updates Based on Risk (see URL in Notes) guidance and CISA’s “Forensics Triage Requirements” (see URL in Notes). Follow applicable BOD 26-04 guidance for cloud services or discontinue use of the product if mitigations are unavailable. Stakeholders are responsible for evaluating each asset's internet exposure and ensuring adherence to BOD 26-04 patching guidelines.
Source-reported weakness categories
CWE-177
Source-specific records & product guidance
Sources retain their own attribution and scoring. Follow the original record to confirm affected versions, fixed releases, and configuration conditions.
NIST National Vulnerability Database · NVD-CVE-2026-76504
Open original source · Updated Oct 02, 2026
Only CPE matches marked vulnerable=true are indexed. AND/OR platform conditions must be checked in the original NVD record.
| Vendor | Product / association | Version / bounds |
|---|---|---|
| cisco | catalyst_sd-wan_manager | * {"versionStartIncluding":"26.1","versionEndExcluding":"26.1.2.1"} |
| cisco | catalyst_sd-wan_manager | 26.2 |
CERT-FR all advisories · RSS-1687df44b7955f2dddfed78c4d4b3c358ea
Open original source · Updated Sep 30, 2026
Vulnérabilité dans Cisco Catalyst SD-WAN (01 octobre 2026)
CVE mention in publisher metadata; check the original affected versions.
Rapid7 Blog · RSS-e6b4659f60517e3904adf3788f5d5c65771
Open original source · Updated Sep 30, 2026
Critical Cisco Catalyst SD-WAN Manager API authentication bypass exploited in the wild (CVE-2026-76504)
CVE mention in publisher metadata; check the original affected versions.
Original records & references
- NIST NVD record
- CVE Program record
- CISA KEV catalog entry
- sec.cloudapps.cisco.com — Mitigation, Vendor Advisory
- www.cisa.gov — US Government Resource
PUBLISHED 2026-09-30T09:17:20-04:00
MODIFIED 2026-10-02T20:16:39-04:00
INGESTED 2026-10-06T11:44:58-04:00