---
cve: "CVE-2026-67294"
severity: "CRITICAL"
cvss: 9.3
epss: "27%"
vendor: "FreeRDP"
kev: false
exploited: false
published: "2026-08-01 13:16:58"
tags: [cve, security, critical]
source: tsecurity.de CVE-Dossier
exported: "2026-09-04T07:38:48+02:00"
---

# CVE-2026-67294

> 9.3 CRITICAL · 🧪 PoC

## Beschreibung

FreeRDP before 3.29.0 improperly validates the Extended Key Usage (EKU) purpose of the peer certificate during client-side server TLS authentication. In x509_utils_verify(), when server-purpose (X509_PURPOSE_SSL_SERVER) verification fails, the code falls back to client-purpose and any-purpose verification, so a trusted, hostname-matching certificate valid only for clientAuth can be accepted as the RDP server certificate. In environments relying on EKU separation between client and server certificates, this allows a clientAuth-only certificate issued by a trusted CA to bypass server certificate purpose validation.

## CVSS-Vektor

```
CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:H/VI:H/VA:H/SC:N/SI:N/SA:N
```

| Metrik | Wert | Bewertung |
|---|---|---|
| AV Angriffsvektor | Netzwerk | bad |
| AC Komplexität | Gering | bad |
| PR Privilegien | Keine | bad |
| UI Interaktion | Keine | bad |

## Patch verfügbar (OSV)

- 743f437f434c6814d3ba265c75cab14673bc2911 (Commit)
- f3b4347105114fe7453828736bea069999af319f (Commit)

## Referenzen

- <https://github.com/FreeRDP/FreeRDP/security/advisories/GHSA-89c6-jjrw-96h4>
- <https://github.com/FreeRDP/FreeRDP/commit/f3b4347105114fe7453828736bea069999af319f>
- <https://www.vulncheck.com/advisories/freerdp-before-tls-certificate-eku-bypass>

---
_Exportiert aus dem [tsecurity.de CVE-Dossier](https://tsecurity.de/cve?cve=CVE-2026-67294) · Datenquellen: EUVD (ENISA), NVD, OSV, CISA KEV, FIRST EPSS, Exploit-DB, BSI BITS_