Critical Cisco Catalyst SD-WAN Zero-Day Under Active Exploitation

**Cisco issues emergency patch for CVE-2026-76504:** A critical (CVSS 9.8) authentication-bypass zero-day in Cisco Catalyst SD-WAN Manager is being actively exploited in the wild, allowing unauthenticated attackers to gain admin API access and potentially take over affected networks; Cisco and CISA recommend immediate upgrade to fixed releases and auditing of exposed systems, with no viable workaround other than applying the patch.