TI-2025-08701 Aliases CVE-2025-9495 GHSA-jmw7-g9jf-52hh

Viessmann Vitogate 300 Authentication Bypass

LOW 39CWE-602Published 2025-09-23 · Updated 2025-09-23

Key facts

Attack vector: Adjacent network
Privileges required: None
User interaction: None
Attack complexity: Low
Attack requirements: None
Impact type: —
Confidentiality · integrity · availability: High · High · High
Fix status: Fixed

Attack profile from CVSS 4.0 · CNA. Fix status from CNA.

Summary

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.

Why it matters now

Exploitation None reported CISA SSVC · not in CISA KEV

EPSS 0.00241 15th percentileScored 2026-11-07

Fix Fixed Vitogate 300 (Viessmann): 3.0.0.0

SSVC decision points

CISA ADP · SSVC 2.0.3

Exploitation: None
Automatable: No
Technical impact: Total

The decision (Track, Attend, Act) also depends on your mission and well-being impact; see CISA's SSVC guide.

Affected products

Vendor	Product	Affected versions	Fixed in	Status	Source
Viessmann	Vitogate 300	1 to before 3.0.0.0	3.0.0.0	Patch available	CNA

Vitogate 300 VendorViessmann Affected 1 to before 3.0.0.0 Fixed in 3.0.0.0 Patch available CNA

Remediation

Fix · CNA Vitogate 300 (Viessmann) Fixed in 3.0.0.0

Timeline

2026-10-02 Threatist record created from CVE-2025-9495
2026-10-03 Alias added: GHSA-jmw7-g9jf-52hh

References

Other 1

https://https://www.corporate.carrier.com/product-security/advisories-resources/

TI-2023-24609 In Vitogate 300 2.1.3.0, /cgi-bin/vitogate.cgi allows an unauthenticated attacker to… CVSS 3.1CRITICAL 9.8
TI-2023-04802 Viessmann Vitogate 300 Web Management Interface vitogate.cgi isValidUser hard-coded password CVSS 3.1CRITICAL 9.8
TI-2023-05245 Viessmann Vitogate 300 direct request CVSS 3.1MEDIUM 6.5
TI-2025-08700 Viessmann Vitogate 300 OS Command Injection CVSS 4.0HIGH 8.5

Sources

This product uses the NVD API but is not endorsed or certified by the NVD. Sources and licences