ZITADEL user enumeration vulnerability in login UI
Published Aug 22, 2025
5.3
MEDIUMCVSS 3.1
EPSS 0.38%
Description
The open-source identity infrastructure software Zitadel allows administrators to disable the user self-registration. Versions 4.0.0 to 4.0.2, 3.0.0 to 3.3.6, and all versions prior to 2.71.15 are vulnerable to a username enumeration issue in the login interface. The login UI includes a security feature, Ignoring unknown usernames, that is intended to prevent username enumeration by returning a generic response for both valid and invalid usernames. This vulnerability allows an unauthenticated attacker to bypass this protection by submitting arbitrary userIDs to the select account page and distinguishing between valid and invalid accounts based on the system's response. For effective exploitation, an attacker needs to iterate through possible userIDs, but the impact can be limited by implementing rate limiting or similar measures. The issue has been patched in versions 4.0.3, 3.4.0, and 2.71.15.
Affected products
-
- Version < 2.71.15StatusaffectedConstraints-
- Version >= 3.0.0, < 3.4.0StatusaffectedConstraints-
- Version >= 4.0.0, < 4.0.3StatusaffectedConstraints-
- Version
No data.
No Red Hat product state for this CVE.
No package ranges for this CVE.
Remediation
No remediation recorded yet.
Metrics
No CVSS v4.0 score for this CVE.
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:N/A:N
No CVSS v3.0 score for this CVE.
No CVSS v2.0 score for this CVE.
This CVE is not in the KEV list.
CISA SSVC (Vulnrichment)
Stakeholder-Specific Vulnerability Categorization from CISA ADP.
Exploitation
NoneAutomatable
NoTechnical Impact
PartialDecision
n/aAssessed Aug 22, 2025 · SSVC 2.0.3
Estimated probability of exploitation in the wild in the next 30 days (FIRST EPSS). As of Oct 3, 2026.
Score over time
2025–2026- EPSS v4
- EPSS v5
Percentile over time
- EPSS v4
- EPSS v5
Table of values (3 key points)
Flat stretches are collapsed; showing up to 120 newest points.
| Date | Score | Percentile | Model |
|---|---|---|---|
| Oct 3, 2026 | 0.38% (0.00375) | 29.17th | v5 (v2026.06.15) |
| Jun 15, 2026 | 0.35% (0.00350) | 26.63th | v5 (v2026.06.15) |
| Aug 23, 2025 | 0.04% (0.00044) | 12.37th | v4 (v2025.03.14) |
References (6)
- https://github.com/zitadel/zitadel/commit/7abe759c95cb360524d88b51744d03cbb6e4dcdb x_refsource_MISCPatch
- https://github.com/zitadel/zitadel/releases/tag/v2.71.15 x_refsource_MISCRelease Notes
- https://github.com/zitadel/zitadel/releases/tag/v3.4.0 x_refsource_MISCRelease Notes
- https://github.com/zitadel/zitadel/releases/tag/v4.0.3 x_refsource_MISCRelease Notes
- https://github.com/zitadel/zitadel/security/advisories/GHSA-g9c3-xh6v-fr86 x_refsource_CONFIRMVendor Advisory
- https://zitadel.com/docs/self-hosting/manage/production#limits-and-quotas x_refsource_MISCProduct
| Link | Providers | Tags |
|---|---|---|
| https://github.com/zitadel/zitadel/commit/7abe759c95cb360524d88b51744d03cbb6e4dcdb | x_refsource_MISCPatch | |
| https://github.com/zitadel/zitadel/releases/tag/v2.71.15 | x_refsource_MISCRelease Notes | |
| https://github.com/zitadel/zitadel/releases/tag/v3.4.0 | x_refsource_MISCRelease Notes | |
| https://github.com/zitadel/zitadel/releases/tag/v4.0.3 | x_refsource_MISCRelease Notes | |
| https://github.com/zitadel/zitadel/security/advisories/GHSA-g9c3-xh6v-fr86 | x_refsource_CONFIRMVendor Advisory | |
| https://zitadel.com/docs/self-hosting/manage/production#limits-and-quotas | x_refsource_MISCProduct |
Change history (0)
No recorded changes yet.