CVE-2026-20211

published 2026-09-16

CVE-2026-20211: A vulnerability in Cisco ISE could allow an authenticated, remote attacker to execute arbitrary commands on the underlying operating system of an affected…

Priority P2 64 critical 9.1 CVSS 3.1

AV N AC L PR H UI N S C C H I H A H

A vulnerability in Cisco ISE could allow an authenticated, remote attacker to execute arbitrary commands on the underlying operating system of an affected device. To exploit this vulnerability, the attacker must have valid high-privileged administrative credentials.

This vulnerability is due to insecure deserialization of Java objects by the affected software. An attacker could exploit this vulnerability by sending a crafted serialized Java object to an affected device. A successful exploit could allow the attacker to obtain user-level access to the underlying operating system and then 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.

Affected

47 ranges · showing 25

Vendor	Product	Version range	Fixed in
cisco	cisco_identity_services_engine_software	—	—
cisco	cisco_identity_services_engine_software	—	—
cisco	cisco_identity_services_engine_software	—	—
cisco	cisco_identity_services_engine_software	—	—
cisco	cisco_identity_services_engine_software	—	—
cisco	cisco_identity_services_engine_software	—	—
cisco	cisco_identity_services_engine_software	—	—
cisco	cisco_identity_services_engine_software	—	—
cisco	cisco_identity_services_engine_software	—	—
cisco	cisco_identity_services_engine_software	—	—
cisco	cisco_identity_services_engine_software	—	—
cisco	cisco_identity_services_engine_software	—	—
cisco	cisco_identity_services_engine_software	—	—
cisco	cisco_identity_services_engine_software	—	—
cisco	cisco_identity_services_engine_software	—	—
cisco	cisco_identity_services_engine_software	—	—
cisco	cisco_identity_services_engine_software	—	—
cisco	cisco_identity_services_engine_software	—	—
cisco	cisco_identity_services_engine_software	—	—
cisco	cisco_identity_services_engine_software	—	—
cisco	cisco_identity_services_engine_software	—	—
cisco	cisco_identity_services_engine_software	—	—
cisco	cisco_identity_services_engine_software	—	—
cisco	cisco_identity_services_engine_software	—	—
cisco	cisco_identity_services_engine_software	—	—

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