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CVE-2026-20192: Cisco Identity Services Engine: Improper Access Control

CVE-2026-20192 is rated critical with a CVSS v3.1 base score of 10.0 and affects Cisco Identity Services Engine, along with 1 other product in NVD’s configuration data. Per its scoring, it can be exploited over the network, without authentication, without any user interaction. The scored impact on confidentiality, integrity and availability is the highest available.

Vulnerability description

As part of Cisco's ongoing commitment to proactive security and product quality, the Cisco Identity Services Engine (ISE) and Cisco ISE Passive Identity Connector (ISE-PIC) engineering teams have conducted a comprehensive internal security review. This review resulted in a software hardening release that addresses multiple internally discovered vulnerabilities. The vulnerabilities tracked by CVE-2026-20192 are related to improper access control issues that are grouped under the Common Weakness Enumeration (CWE) Pillar CWE-284.

Severity breakdown

CVSS v3.1 10.0: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:C/C:H/I:H/A:H

  • Attack vector: Network. Exploitable remotely over the network, with no need for local or physical access.
  • Attack complexity: Low. No special conditions; the attack can be repeated reliably.
  • Privileges required: None. No account or prior access is needed.
  • User interaction: None. No action from any user is needed.
  • Scope: Changed. Impact reaches beyond the vulnerable component to other resources.
  • Confidentiality impact: High. Total loss of confidentiality; sensitive data can be fully disclosed.
  • Integrity impact: High. Total loss of integrity; data or system state can be fully modified.
  • Availability impact: High. Total loss of availability; the component can be shut down.

Underlying weakness

CWE-284: Improper Access Control

The product does not restrict or incorrectly restricts access to a resource from an unauthorized actor.

Affected products

  • Cisco Identity Services Engine: from 3.1.0 before 3.3.0; 3.3.0 patch1; 3.3.0 patch10; 3.3.0 patch11; 3.3.0 patch2; 3.3.0 patch3; 3.3.0 patch4; 3.3.0 patch5; 3.3.0 patch6; 3.3.0 patch7; 3.3.0 patch8; 3.3.0 patch9
  • Cisco Identity Services Engine Passive Identity Connector: from 3.1.0 before 3.3.0; 3.3.0 patch1; 3.3.0 patch10; 3.3.0 patch11; 3.3.0 patch2; 3.3.0 patch3; 3.3.0 patch4; 3.3.0 patch5; 3.3.0 patch6; 3.3.0 patch7; 3.3.0 patch8; 3.3.0 patch9

References