CVE-2025-9495

Viessmann Vitogate 300 Authentication Bypass

Published Sep 23, 2025 CVSS 4.0 · 8.7 High EPSS < 1% KEV · Not listed
Description
The Vitogate 300 web interface fails to enforce proper server-side authentication and relies on frontend-based authentication controls. This allows an attacker to simply modify HTML elements in the browser’s developer tools to bypass login restrictions. By removing specific UI elements, an attacker can reveal the hidden administration menu, giving them full control over the device.

Remediation

Vendor Solution

These vulnerabilities have been fixed with Vitogate 300 software version 3.1.0.1. Customers are strongly encouraged to upgrade by downloading software version 3.1.0.1 or newer at the Vitogate 300 website.

Tracking

Sign in to view the affected projects.

Advisories

Source ID Title
EUVD EUVD EUVD-2025-30428 The Vitogate 300 web interface fails to enforce proper server-side authentication and relies on frontend-based authentication controls. This allows an attacker to simply modify HTML elements in the browser’s developer tools to bypass login restrictions. By removing specific UI elements, an attacker can reveal the hidden administration menu, giving them full control over the device.
History
Type Values Removed Values Added
First Time appeared Viessmann
Viessmann vitogate 300
Vendors & Products Viessmann
Viessmann vitogate 300
Type Values Removed Values Added
Metrics ssvc

{'options': {'Automatable': 'no', 'Exploitation': 'none', 'Technical Impact': 'total'}, 'version': '2.0.3'}

Type Values Removed Values Added
Description The Vitogate 300 web interface fails to enforce proper server-side authentication and relies on frontend-based authentication controls. This allows an attacker to simply modify HTML elements in the browser’s developer tools to bypass login restrictions. By removing specific UI elements, an attacker can reveal the hidden administration menu, giving them full control over the device.
Title Viessmann Vitogate 300 Authentication Bypass
Weaknesses CWE-602
References
Metrics cvssV4_0

{'score': 8.7, 'vector': 'CVSS:4.0/AV:A/AC:L/AT:N/PR:N/UI:N/VC:H/VI:H/VA:H/SC:N/SI:N/SA:N'}

Weaknesses

Sources

Status
PUBLISHED
Assigner
Carrier
Published
Updated
Sep 23, 2025, 1:33 PM
Reserved
Aug 26, 2025, 5:40 PM
Status
Deferred
Published
Sep 23, 2025, 2:15 AM
Modified
Oct 11, 2026, 8:10 PM