Alert - AL26-021 - Vulnerabilities Impacting Cisco Identity Services Engine (ISE) and Cisco ISE Passive Identity Connector (ISE-PIC) - CVE-2026-20192, CVE-2026-76423 and CVE-2026-76460

Number: AL26-021
Date: September 17, 2026

Audience

This Alert is intended for IT professionals and managers.

Purpose

An Alert is used to raise awareness of a recently identified cyber threat that may impact cyber information assets, and to provide additional detection and mitigation advice to recipients. The Canadian Centre for Cyber Security ("Cyber Centre") is also available to provide additional assistance regarding the content of this Alert to recipients as requested.

Details

The Canadian Centre for Cyber Security (Cyber Centre) is aware of multiple vulnerabilities impacting Cisco Identity Services Engine (ISE) and Cisco ISE Passive Identity Connector (ISE-PIC)^{Footnote 1}.

Successful exploitation could allow unauthenticated attackers to bypass authentication controls, gain administrative access, access or modify sensitive data, and potentially compromise affected systems.

In response to the vendor advisory released on September 16, 2026, the Cyber Centre released AV26-932 on September 17, 2026^{Footnote 2}.

Tracked as CVE-2026-20192^{Footnote 3}, this vulnerability is an Improper Access Control vulnerability (CWE-284)^{Footnote 4} that may allow an unauthenticated attacker to bypass security controls, access sensitive information, modify system configurations, and impact system availability.

Tracked as CVE-2026-76423^{Footnote 5}, this vulnerability is an Authentication Bypass by Spoofing vulnerability (CWE-290)^{Footnote 6} that may enable the attacker to read and modify ISE configuration and identity data with administrative privileges.

Tracked as CVE-2026-76460^{Footnote 7}, this vulnerability is an Incorrect Use of Privileged APIs vulnerability (CWE-648)^{Footnote 8} that may allow an attacker to gain unauthorized access to the affected device by bypassing the web-based management interface. Cisco has confirmed active exploitation of this vulnerability.

On September 16, 2026, Cybersecurity and Infrastructure Security Agency (CISA) added CVE-2026–76460 to their Known Exploited Vulnerabilities (KEV) Database^{Footnote 9}.

Suggested actions

The Cyber Centre strongly recommends that organizations running Cisco ISE and ISE-PIC upgrade to the vendor-supported fixed software versions identified below.

The Cyber Centre also recommends organizations to:

• Apply vendor-provided security updates immediately. Cisco has released fixes for all three vulnerabilities.
• Prioritize remediation of CVE-2026-76460 due to confirmed in-the-wild exploitation.
• Review access logs for indicators of compromise (IoC), particularly suspicious usernames and unexpected API activity.
• Restrict access to management interfaces through access control lists (ACL), network segmentation, and trusted administration networks where feasible.
• If compromise is suspected, re-image affected nodes and restore from known-good backups, as attackers may obtain elevated privileges and remove evidence of exploitation.
• Monitor firewall, network, and authentication logs for anomalous activity associated with affected systems.

Note: Organizations operating Common Criteria^{Footnote 10} evaluated configurations should review Cisco's advisory and apply the recommended updates in accordance with their change management and certification requirements.

In addition, the Cyber Centre strongly recommends that organizations review and implement the Cyber Centre's Top 10 IT Security Actions^{Footnote 11} with an emphasis on the following topics:

• Consolidating, monitoring, and defending Internet gateways
• Patch operating systems and applications
• Harden operating systems and applications
• Isolate web-facing applications

Should activity matching the content of this alert be discovered, recipients are encouraged to report via My Cyber Portal, or email contact@cyber.gc.ca.

References