CVE-2025-9495 Viessmann Vitogate 300 Authentication Bypass
Attackers can bypass login by modifying HTML elements to access the hidden administration menu and gain full control of the device.
- Exploited in the wild
- Not known
- Login needed
- Not needed
- Attackable
- Local or same network only
- Victim action needed
- Not needed
- Fix
- None listed
What is CVE-2025-9495?
CVE-2025-9495 is a high-severity authentication bypass vulnerability in Viessmann Vitogate 300, published on 23 Sep 2025. It can only be exploited from the same machine or local network, with no action from the victim.
Official 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.
Weakness: CWE-602
Which versions are affected by CVE-2025-9495?
How do I fix CVE-2025-9495?
No fix has been published for CVE-2025-9495 yet. Limit exposure of the affected software until one is available.
Upgrade, and rotate credentials and sessions that may have been exposed. More about Authentication bypass.
Is CVE-2025-9495 being exploited?
There is no known exploitation of CVE-2025-9495 in the wild and no public exploit code.
Sources
Also known as GHSA-jmw7-g9jf-52hh.