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.
Affected versions
| Package | Affected | Fixed in |
|---|---|---|
| Cisco ISE Passive Identity Connector Product | <= 3.4.0 | No fix yet |
| Cisco Identity Services Engine Software Product | <= 3.4 Patch 4 | No fix yet |
| <= 3.4 Patch 5 | No fix yet | |
| <= 3.5 Patch 3 | No fix yet | |
| <= 3.4 Patch 6 | No fix yet |
Details and references
- CVSS 3.1
- CVSS:3.1/AV:N/AC:L/PR:H/UI:N/S:C/C:H/I:H/A:H
- Severity from
- the vendor (its own CVE record or advisory)
- Weakness
- CWE-78
More Cisco advisories
All Cisco| Date | Advisory | Severity | Fixed in |
|---|---|---|---|
| Sep 16 | Cisco ISE Passive Identity Connector: SQL injection | Medium4.9 | No fix yet |
| Sep 16 | Cisco ISE Passive Identity: authenticated, remote attacker could conduct an SQL... | Medium4.9 | No fix yet |
| Sep 16 | Cisco ISE Passive Identity: authenticated, remote attacker could conduct an SQL... | Medium4.9 | No fix yet |
| Sep 16 | Cisco ISE Passive Identity Connector: authentication bypass | Critical10.0 | No fix yet |
| Sep 16 | Cisco ISE Passive Identity Connector: XML external entity | Medium4.9 | No fix yet |
| Sep 16 | Cisco ISE Passive Identity Connector: missing authentication | Medium5.3 | No fix yet |