Vulnerability · Published Sep 16, 2026 · Assigned by cisco
CVE-2026-20237Cisco Identity Services Engine Hardening Release - Input Validation Vulnerabilities
Critical 9.1
In plain English
A critical-severity improper input validation 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 0.5% (higher than 41% of all known vulnerabilities).
Official 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-2026-20237 are related to improper input validation issues that are grouped under the Common Weakness Enumeration (CWE) Pillar CWE-20.
Affected products (as reported)
| Vendor | Product | Versions |
|---|---|---|
| Cisco | Cisco Identity Services Engine Software | 3.1.03.1.0 p13.1.0 p33.1.0 p23.2.03.1.0 p43.1.0 p53.2.0 p1 |
| Cisco | Cisco ISE Passive Identity Connector | 3.2.03.1.03.3.03.4.03.5.0 |
Weakness: CWE-20 · Vector: CVSS:3.1/AV:N/AC:L/PR:H/UI:N/S:C/C:H/I:H/A:H