CVE-2025-67494: ZITADEL Vulnerable to Unauthenticated Full-Read SSRF via V2 Login
Summary
Zitadel is vulnerable to an unauthenticated, full-read SSRF vulnerability. An unauthenticated remote attacker can force Zitadel into making HTTP requests to arbitrary domains, including internal addresses. The server then returns the upstream response to the attacker, enabling data exfiltration from internal services.
Impact
ZITADEL Login UI (V2) was vulnerable to service URL manipulation through the x-zitadel-forward-host header. The service URL resolution logic treated the header as a trusted fallback for all deployments, including self-hosted instances. This allowed unauthenticated attacker to force the server to make outbound requests and read the responses, reaching internal services, exfiltrating data, and bypassing IP-based or network-segmentation controls. Affected Versions
Systems using the login UI (v2) and running one of the following versions are affected: - v4.x: 4.0.0-rc.1 through 4.7.0
Patches
The vulnerability has been addressed in the latest release. The patch resolves the issue by correctly validating the x-zitadel-forward-host, resp. all forwarded headers against the instance domains and trusted domains. It's no longer used to route traffic to the Zitadel API.
Before you upgrade, ensure that: - the ZITADELAPIURL is set and is pointing to your instance, resp. system in multi-instance deployments. - the HTTP host (or a x-forwarded-host) is passed in your reverse proxy to the login UI. - a x-zitadel-instance-host (or x-zitadel-forward-host) is set in your reverse for multi-instance deployments. If you're running a single instance solution, you don't need to take any actions.
Fixed versions: - 4.x: Upgrade to >=4.7.1
Workarounds
The recommended solution is to update ZITADEL to a patched version.
A ZITADEL fronting proxy can be configured to delete all x-zitadel-forward-host header values or set it to the requested host before sending requests to ZITADEL self-hosted environments.
Questions
If you have any questions or comments about this advisory, please email us at security@zitadel.com
Credits
Thanks to Amit Laish – GE Vernova for finding and reporting the vulnerability.
Other sources
ZITADEL is an open-source identity infrastructure tool. Versions 4.7.0 and below are vulnerable to an unauthenticated, full-read SSRF vulnerability. The ZITADEL Login UI (V2) treats the x-zitadel-forward-host header as a trusted fallback for all deployments, including self-hosted instances. This allows an unauthenticated attacker to force the server to make HTTP requests to arbitrary domains, such as internal addresses, and read the responses, enabling data exfiltration and bypassing network-segmentation controls. This issue is fixed in version 4.7.1.
— MITRE
Affected Software
Remediation
Event History
Frequently Asked Questions
What is the severity of CVE-2025-67494?
CVE-2025-67494 is classified as a critical vulnerability due to its potential for unauthorized access and data exfiltration.
Who is affected by CVE-2025-67494?
CVE-2025-67494 affects Zitadel versions prior to 1.80.0-v2.20.0.20251208091519-4c879b47334e and versions between 4.0.0-rc.1 and 4.7.1.
How do I fix CVE-2025-67494?
To remediate CVE-2025-67494, upgrade Zitadel to version 1.80.0-v2.20.0.20251208091519-4c879b47334e or a secure version within the specified range.
What type of vulnerability is CVE-2025-67494?
CVE-2025-67494 is an unauthenticated server-side request forgery (SSRF) vulnerability.
What can an attacker do with CVE-2025-67494?
An attacker exploiting CVE-2025-67494 can make Zitadel send HTTP requests to arbitrary domains, potentially leading to data leakage.