CVE-2025-31124 Zitadel allows User Enumeration by loginname attribute normalization

Medium 5.3 Published 31 Mar 2025 Updated 31 Mar 2025

Attackers can enumerate valid usernames in Zitadel by exploiting username normalization flaws, even when the 'Ignoring unknown usernames' security setting is enabled.

Exploited in the wild: Not known
Login needed: Not needed
Attackable: Over the internet
Victim action needed: Not needed
Fix: None listed

What is CVE-2025-31124?

CVE-2025-31124 is a medium-severity vulnerability in zitadel, published on 31 Mar 2025. An attacker can exploit it over the internet without logging in, with no action from the victim.

Official 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.

Weakness: CWE-204, CWE-203, CWE-200

Which versions are affected by CVE-2025-31124?

It affects 1 product.

Products include Zitadel Zitadel.

How do I fix CVE-2025-31124?

No fix has been published for CVE-2025-31124 yet. Limit exposure of the affected software until one is available.

Is CVE-2025-31124 being exploited?

There is no known exploitation of CVE-2025-31124 in the wild and no public exploit code.

Sources

Also known as GHSA-67m4-8g4w-633q.