Cisco issues emergency patch for critical zero-day vulnerability

Cisco: Cisco Systems develops networking hardware, software, and security solutions for enterprises worldwide. In this incident, the company issued emergency patches for a critical zero-day vulnerability in its Identity Services Engine after confirming active exploitation in the wild. CVE-2026-76460: CVE-2026-76460 is a critical authentication bypass flaw affecting an API endpoint in Cisco Identity Services Engine. The vulnerability allows attackers to gain unauthorized access and has been exploited as a zero-day, prompting an immediate patch release and addition to CISA’s Known Exploited Vulnerabilities catalog. Identity Services Engine: Cisco Identity Services Engine (ISE) is an enterprise network access control and policy enforcement platform. The product, along with its Passive Identity Connector variant, is directly impacted by the actively exploited CVE-2026-76460 vulnerability regardless of configuration. ISE Passive Identity Connector: ISE Passive Identity Connector (ISE-PIC) is a Cisco component that enables passive identity collection for network access policies. It is affected by the same critical authentication bypass vulnerability as the main ISE appliance and requires the same patched versions for remediation. Government Action: CISA added the vulnerability to its Known Exploited Vulnerabilities catalog and directed federal agencies to apply patches within three days. Vulnerability Response: Cisco PSIRT confirmed active exploitation of the flaw and strongly recommended immediate upgrades to fixed releases.