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

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

- **Severity:** Medium 5.3 (`CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:N/A:N`)
- **Exploited in the wild:** Not known
- **Login needed:** Not needed
- **Attackable:** Over the internet
- **Victim action needed:** Not needed
- **Fix available:** No
- **Published:** 31 Mar 2025
- **Updated:** 31 Mar 2025
- **Also known as:** GHSA-67m4-8g4w-633q

## 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 (Observable Response Discrepancy), CWE-203 (Observable Discrepancy), CWE-200 (Exposure of Sensitive Information to an Unauthorized Actor)

## Which versions are affected by CVE-2025-31124?

It affects 1 product.


Products: 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.

## Other vulnerabilities in zitadel

- [CVE-2026-29191](https://insights.sbomify.com/CVE-2026-29191/): ZITADEL: 1-Click Account Takeover via XSS in /saml-post Endpoint (critical 9.3)
- [CVE-2025-67494](https://insights.sbomify.com/CVE-2025-67494/): ZITADEL Vulnerable to Unauthenticated Full-Read SSRF via V2 Login (critical 9.3)
- [CVE-2025-27507](https://insights.sbomify.com/CVE-2025-27507/): IDOR Vulnerabilities in ZITADEL's Admin API that Primarily Impact LDAP Configurations (critical 9.0)
- [CVE-2025-64103](https://insights.sbomify.com/CVE-2025-64103/): Zitadel Bypass Second Authentication Factor (high 8.7)
- [CVE-2025-31123](https://insights.sbomify.com/CVE-2025-31123/): Zitadel Expired JWT Keys Usable for Authorization Grants (high 8.7)

## Fix prompt for AI coding agents

```text
Check this codebase for CVE-2025-31124 and fix it if it is affected.

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

Affected product: zitadel. No package-level version data is available, so check the vendor advisory linked from the reference page.

Task:
1. Search the dependency manifests and lockfiles (for example package.json, package-lock.json, requirements.txt, poetry.lock, uv.lock, pom.xml, build.gradle, go.mod, Cargo.lock, Gemfile.lock) and any Dockerfiles for the affected packages, including transitive dependencies.
2. If an affected version is in use, upgrade it to the fixed version for its release line with the project's package manager, so the lockfile is regenerated. Prefer the smallest upgrade that fixes it.
3. If there is no fix, or the upgrade would break the build, do not guess: explain the risk and the safest workaround instead.
4. Run the tests and summarise what changed and why.
5. If nothing in the project is affected, say so and change nothing.

Reference: https://insights.sbomify.com/CVE-2025-31124/ (Markdown: https://insights.sbomify.com/CVE-2025-31124/index.md)
```

## Sources

- CVE record: https://www.cve.org/CVERecord?id=CVE-2025-31124
- NVD: https://nvd.nist.gov/vuln/detail/CVE-2025-31124
- OSV: https://osv.dev/vulnerability/CVE-2025-31124

---
From sbomify Insights: https://insights.sbomify.com/CVE-2025-31124/
Summaries are generated and may contain mistakes; the official description above is the record.