CVE-2026-76504: Cisco SD-WAN Flaw Exploited

**CVE-2026-76504 — Cisco Catalyst SD-WAN Manager authentication bypass:** A critical (CVSS 9.8) authentication-bypass vulnerability in Cisco SD-WAN Manager (vManage) permits unauthenticated administrative API access via inconsistent URI decoding; Cisco confirmed active exploitation in September 2026 and CISA added the CVE to its KEV catalog with an October 3, 2026 remediation deadline. The advisory lists affected releases and fixes, detection indicators (e.g., encoded j_security_check requests and Snort rule 67179), and recommends immediate evidence collection, upgrading to fixed releases, constrained management access, and submitting admin-tech bundles to Cisco TAC for compromise assessment.