---
cve: "CVE-2026-18211"
severity: "MEDIUM"
cvss: 4.2
epss: "18%"
vendor: "Generic Security"
kev: false
exploited: false
published: "2026-07-31 08:16:27"
tags: [cve, security, medium]
source: tsecurity.de CVE-Dossier
exported: "2026-09-03T03:03:18+02:00"
---

# CVE-2026-18211

> 4.2 MEDIUM

## Beschreibung

A flaw was found in the secure-client-uris client policy executor within Keycloak core services. This component is responsible for enforcing security requirements on client configurations, such as requiring encrypted connections for redirect URIs. Due to an improper check that only looks at the start of a web address rather than properly verifying the host, an attacker can bypass these security restrictions by using a specially crafted domain name. This could allow an attacker to intercept sensitive authentication codes over unencrypted connections.

## CVSS-Vektor

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

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

## Referenzen

- <https://access.redhat.com/security/cve/CVE-2026-18211>
- <https://bugzilla.redhat.com/show_bug.cgi?id=2508306>

---
_Exportiert aus dem [tsecurity.de CVE-Dossier](https://tsecurity.de/cve?cve=CVE-2026-18211) · Datenquellen: EUVD (ENISA), NVD, OSV, CISA KEV, FIRST EPSS, Exploit-DB, BSI BITS_