Cisco Catalyst SD-WAN Manager: authentication bypass
Critical9.8CVE-2026-76504 · Published Sep 30, 2026 · updated Oct 1, 2026
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.
Affected versions
| Package | Affected | Fixed in |
|---|---|---|
| Cisco Catalyst SD-WAN Manager Product | <= 18.3.6 | No fix yet |
| <= 18.3.7 | No fix yet | |
| <= 18.3.8 | No fix yet | |
| <= 17.2.10 | No fix yet |
Details and references
- CVSS 3.1
- CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H
- Severity from
- the vendor (its own CVE record or advisory)
- Weakness
- CWE-177
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