CVE-2026-119127

ZITADEL 4.0.0 before 4.19.5 contains a host header injection vulnerability in the Login V2 UI that allows unauthenticated attackers to poison password-reset, invite, and email-verification links by supplying untrusted x-zitadel-public-host, x-zitadel-forward-host, or x-forwarded-host headers. Attackers knowing a victim's login name can point the links in genuine emails at their host, harvest the single-use codes when the links are opened, and take over accounts including instance administrators.

CVSS v3 8.1 HIGH

8.1^/10

CVSS v3 : HIGH

Vector :

Exploitability : 2.8 / Impact : 5.2

Attack Vector NETWORK

Attack Complexity LOW

Privileges Required NONE

User Interaction REQUIRED

Confidentiality Impact HIGH

Integrity Impact HIGH

Availability Impact NONE

Scope UNCHANGED

References

Link	Resource
https://github.com/zitadel/zitadel/security/advisories/GHSA-mchc-246r-6m76
https://www.vulncheck.com/advisories/zitadel-4.0.0-before-4.19.5-account-takeover-via-login-v2-host-header-injection

Configurations

No configuration.

History

29 Oct 2026, 16:18

Type	Values Removed	Values Added
New CVE

Information

Published : 2026-10-29 16:18

Updated : 2026-10-29 16:18

NVD link : CVE-2026-119127

Mitre link : CVE-2026-119127

CVE.ORG link : CVE-2026-119127

JSON object : View

Products Affected

No product.

CWE

CWE-640

Weak Password Recovery Mechanism for Forgotten Password

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