---
cve: "CVE-2026-11405"
severity: "CRITICAL"
cvss: 9.8
epss: "1.6%"
vendor: "Tenda"
kev: false
exploited: false
published: "2026-07-06 20:16:29"
tags: [cve, security, critical]
source: tsecurity.de CVE-Dossier
exported: "2026-09-03T00:31:28+02:00"
---

# CVE-2026-11405

> 9.8 CRITICAL

## Beschreibung

The web server binary /bin/httpd contains a hidden backdoor authentication mechanism in the login() function at 004c88b8.

- The function contains a normal authentication path using MD5/hash-based password verification (prod_encode64/PasswordToMd5/check_rand_key).
- After normal authentication fails, it calls GetValue("sys.rzadmin.password") to read a backdoor password from the device configuration.
- It performs a direct strcmp() comparison (plaintext, not hashed) between the config value and the user-supplied password.

A successful match grants role=2 (admin-level access) and creates a valid session. The rzadmin username is never checked — any username works with the backdoor

## CVSS-Vektor

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

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

## Referenzen

- <https://cwe.mitre.org/data/definitions/912.html>
- <https://kb.cert.org/vuls/id/213560>
- <https://www.kb.cert.org/vuls/id/213560>

---
_Exportiert aus dem [tsecurity.de CVE-Dossier](https://tsecurity.de/cve?cve=CVE-2026-11405) · Datenquellen: EUVD (ENISA), NVD, OSV, CISA KEV, FIRST EPSS, Exploit-DB, BSI BITS_