CVE-2026-76504

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…

Severity: Critical
CVSS 9.8
EPSS 1.82%
On CISA KEV
Public exploit
P1 · Patch now

Why P1: on CISA KEV.

Description

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 Known Exploited Vulnerability

Added 2026-09-30, remediation due 2026-10-03. Ransomware use: Unknown. 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…

Affected products

cisco catalyst sd-wan manager 26.2
cisco catalyst sd-wan manager < 20.9.10.1
cisco catalyst sd-wan manager >= 20.12, < 20.12.8.2
cisco catalyst sd-wan manager >= 20.15, < 20.15.6.1
cisco catalyst sd-wan manager >= 20.18, < 20.18.4.1
cisco catalyst sd-wan manager >= 26.1, < 26.1.2.1
Cisco Catalyst SD-WAN Manager Version details not specified by CISA

Weakness

CWE-177

CVSS vector

CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H

References

Published 2026-09-30 · updated 2026-10-03 · sources: NVD, GitHub Advisory Database, CISA KEV