Critical

Cisco warns of max severity ISE zero-day exploited in attacks

BleepingComputer

September 17, 2026 at 7:20 AM

Actively Exploited

Zero-day Cisco Exploit Vulnerability Update

Overview

Cisco has issued urgent security updates to fix a serious vulnerability in its Identity Services Engine (ISE), which attackers are currently exploiting. This zero-day flaw poses a significant risk as it allows unauthorized access to networks, making it crucial for organizations using ISE to act quickly. Users of Cisco ISE are particularly vulnerable, as the exploit can lead to data breaches or unauthorized activities within their systems. The company emphasizes the importance of applying the updates immediately to mitigate potential attacks. Security professionals and IT teams should prioritize this update to protect their infrastructures from ongoing threats.

Key Takeaways

Active Exploitation: This vulnerability is being actively exploited by attackers. Immediate action is recommended.
Affected Systems: Cisco Identity Services Engine (ISE)
Action Required: Users should apply the latest security updates provided by Cisco for the Identity Services Engine.
Timeline: Newly disclosed

Original Article Summary

Cisco has released security updates to address a maximum-severity Identity Services Engine vulnerability that attackers are actively exploiting in the wild. [...]

Impact

Cisco Identity Services Engine (ISE)

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

Users should apply the latest security updates provided by Cisco for the Identity Services Engine. Specific patch numbers or versions were not mentioned in the article.

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 Zero-day, Cisco, Exploit, and 2 more.

Read Original Article

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