Zitadel allows User Enumeration by loginname attribute normalization

5.3 CVSS

Vulnerability Description

Zitadel is open-source identity infrastructure software. ZITADEL administrators can enable a setting called "Ignoring unknown usernames" which helps mitigate attacks that try to guess/enumerate usernames. If enabled, ZITADEL will show the password prompt even if the user doesn't exist and report "Username or Password invalid". While the setting was correctly respected during the login flow, the user's username was normalized leading to a disclosure of the user's existence. This vulnerability is fixed in 2.71.6, 2.70.8, 2.69.9, 2.68.9, 2.67.13, 2.66.16, 2.65.7, 2.64.6, and 2.63.9.

Impact Analysis

Refer to official advisory for detailed impact metrics.

Remediation

Ensure systems are updated to the latest vendor-supplied patch levels.

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Credits & Attribution

No credits recorded in the NVD database.

References

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Affected Vendor

zitadel

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Affected Software

zitadel

Vulnerable Versions:

>= 2.62.0, < 2.63.9, >= 2.64.0-rc.1, < 2.64.6, >= 2.65.0-rc.1, < 2.65.7, >= 2.66.0-rc.1, < 2.66.16, >= 2.67.0-rc.1, < 2.67.13, >= 2.68.0-rc.1, < 2.68.9, >= 2.69.0-rc.1, < 2.69.9, >= 2.70.0-rc.1, < 2.70.8, >= 2.71.0-rc.1, < 2.71.6