Vulnerability · Published Sep 16, 2026 · Assigned by cisco
CVE-2026-20306Cisco Identity Services Engine Command Injection Vulnerability
Critical 9.1
In plain English
A critical-severity OS command injection in Cisco Identity Services Engine Software from Cisco. There are no confirmed reports of exploitation so far. The chance it is exploited in the next 30 days is estimated at 1.6% (higher than 75% of all known vulnerabilities).
Official description
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.
Affected products (as reported)
| Vendor | Product | Versions |
|---|---|---|
| Cisco | Cisco Identity Services Engine Software | 3.4 Patch 43.4 Patch 53.5 Patch 33.4 Patch 6 |
| Cisco | Cisco ISE Passive Identity Connector | 3.4.0 |
Weakness: CWE-78 · Vector: CVSS:3.1/AV:N/AC:L/PR:H/UI:N/S:C/C:H/I:H/A:H