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CiscoCVE-2026-20306

Cisco ISE: command injection

Critical9.1CVE-2026-20306 · Published Sep 16, 2026 · updated Sep 17, 2026

A vulnerability in the REST API of Cisco ISE and ISE-PIC could allow an authenticated, remote attacker to perform command injection attacks on the underlying operating system and elevate privileges to root. To exploit this vulnerability, the attacker must have valid administrative credentials. This vulnerability is due to improper validation of user-supplied input. An attacker could exploit this vulnerability by sending crafted commands to the web-based management interface of an affected device. A successful exploit could allow the attacker to execute arbitrary code on the device and elevate privileges to root. In single-node deployments, successful exploitation of this vulnerability could cause the affected ISE node to become unavailable, resulting in a DoS condition. In that condition, endpoints that have not already authenticated would be unable to access the network until the node is restored.

Cisco advisory

Affected versions

PackageAffectedFixed in
Cisco ISE Passive Identity Connector
Product
<= 3.4.0No fix yet
Cisco Identity Services Engine Software
Product
<= 3.4 Patch 4No fix yet
<= 3.4 Patch 5No fix yet
<= 3.5 Patch 3No fix yet
<= 3.4 Patch 6No fix yet
Details and references

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