---
cve: "CVE-2026-20237"
severity: "CRITICAL"
cvss: 9.1
epss: "0.3%"
vendor: "Cisco"
kev: false
exploited: false
published: "2026-09-16 20:17:22"
tags: [cve, security, critical]
source: tsecurity.de CVE-Dossier
exported: "2026-09-20T20:30:34+02:00"
---

# CVE-2026-20237

> 9.1 CRITICAL

## Beschreibung

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.

## CVSS-Vektor

```
CVSS:3.1/AV:N/AC:L/PR:H/UI:N/S:C/C:H/I:H/A:H
```

| Metrik | Wert | Bewertung |
|---|---|---|
| AV Angriffsvektor | Netzwerk | bad |
| AC Komplexität | Gering | bad |
| PR Privilegien | Hoch | good |
| UI Interaktion | Keine | bad |
| S Scope | Verändert | bad |
| C Vertraulichkeit | Hoch | bad |
| I Integrität | Hoch | bad |
| A Verfügbarkeit | Hoch | bad |

## Schwachstellen-Klasse

- **CWE-20** — Improper Input Validation
  The product receives input or data, but it does not validate or incorrectly validates that the input has the properties that are required to process the data safely and correctly.

## Angriffsmuster (CAPEC)

- [CAPEC-10 — Buffer Overflow via Environment Variables](https://capec.mitre.org/data/definitions/10.html) _(Severity: High)_
- [CAPEC-13 — Subverting Environment Variable Values](https://capec.mitre.org/data/definitions/13.html) _(Severity: Very High)_
- [CAPEC-101 — Server Side Include (SSI) Injection](https://capec.mitre.org/data/definitions/101.html) _(Severity: High)_
- [CAPEC-104 — Cross Zone Scripting](https://capec.mitre.org/data/definitions/104.html) _(Severity: High)_
- [CAPEC-108 — Command Line Execution through SQL Injection](https://capec.mitre.org/data/definitions/108.html) _(Severity: Very High)_
- [CAPEC-109 — Object Relational Mapping Injection](https://capec.mitre.org/data/definitions/109.html) _(Severity: High)_
- [CAPEC-110 — SQL Injection through SOAP Parameter Tampering](https://capec.mitre.org/data/definitions/110.html) _(Severity: Very High)_
- [CAPEC-120 — Double Encoding](https://capec.mitre.org/data/definitions/120.html) _(Severity: Medium)_

## ATT&CK-Techniken

- [T1562.003 — Impair Defenses:Impair Command History Logging](https://attack.mitre.org/techniques/T1562/003/)
- [T1574.006 — Hijack Execution Flow:Dynamic Linker Hijacking](https://attack.mitre.org/techniques/T1574/006/)
- [T1574.007 — Hijack Execution Flow:Path Interception by PATH Environment ](https://attack.mitre.org/techniques/T1574/007/)

## Referenzen

- <https://sec.cloudapps.cisco.com/security/center/content/CiscoSecurityAdvisory/cisco-sa-hardening-ise-XU5EwX5T>

---
_Exportiert aus dem [tsecurity.de CVE-Dossier](https://tsecurity.de/cve?cve=CVE-2026-20237) · Datenquellen: EUVD (ENISA), NVD, OSV, CISA KEV, FIRST EPSS, Exploit-DB, BSI BITS_
