Critical

Cisco Warns of New Zero-Day ISE Auth Bypass (CVSS 10.0) Exploited in Active Attacks

The Hacker News

September 17, 2026 at 6:39 AM

Actively Exploited

Overview

Cisco has issued a warning regarding a serious security vulnerability in its Identity Services Engine (ISE), identified as CVE-2026-76460, which carries a maximum CVSS score of 10.0. This flaw allows attackers to bypass authentication without needing any credentials, potentially exposing sensitive systems to unauthorized access. The issue stems from inadequate authentication controls on an API endpoint, making it particularly concerning as it is currently being exploited in the wild. Organizations using Cisco ISE are at risk, and immediate action is necessary to protect their networks from potential breaches. This incident underscores the importance of maintaining up-to-date security measures and promptly addressing vulnerabilities as they are disclosed.

Key Takeaways

Active Exploitation: This vulnerability is being actively exploited by attackers. Immediate action is recommended.
Affected Systems: Cisco Identity Services Engine (ISE), affected versions unspecified.
Action Required: Organizations should urgently apply any available patches for Cisco ISE and review their API security configurations to ensure proper authentication controls are in place.
Timeline: Newly disclosed

Original Article Summary

Cisco has warned of a fresh maximum-severity security flaw impacting Identity Services Engine (ISE) that has come under active exploitation. The vulnerability, tracked as CVE-2026-76460 (CVSS score: 10.0), could allow an unauthenticated, remote attacker to bypass authentication. "This vulnerability is due to insufficient authentication control on an API endpoint," Cisco said. "An attacker

Impact

Cisco Identity Services Engine (ISE), affected versions unspecified.

Exploitation Status

This vulnerability is confirmed to be actively exploited by attackers in real-world attacks. Organizations should prioritize patching or implementing workarounds immediately.

Timeline

Newly disclosed

Remediation

Organizations should urgently apply any available patches for Cisco ISE and review their API security configurations to ensure proper authentication controls are in place. Regular monitoring for unusual activity and implementing network segmentation could also help mitigate risks associated with this vulnerability.

Additional Information

This threat intelligence is aggregated from trusted cybersecurity sources. For the most up-to-date information, technical details, and official vendor guidance, please refer to the original article linked below.

Related Topics: This incident relates to CVE, Zero-day, Cisco, and 1 more.

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