Cisco drops another exploited zero-day, this time a perfect 10

Cisco has warned of a maximum-severity zero-day vulnerability impacting Identity Services Engine (ISE), tracked as CVE-2026-76460. With a CVSS score of 10.0, the flaw is currently under active exploitation. The vulnerability stems from insufficient authentication control on an API endpoint, which could allow an unauthenticated remote attacker to bypass authentication. This critical security issue emerges shortly after another Cisco zero-day, forcing administrators to prioritize urgent patching to secure their network infrastructure against these active attacks.