Zitadel up to 3.4.5/4.9.0 Login Interface response discrepancy

CVSS Meta Temp Score
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CTI Interest Score
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5.2$0-$5k0.00

Summaryinfo

A vulnerability classified as problematic was found in Zitadel up to 3.4.5/4.9.0. Impacted is an unknown function of the component Login Interface. Such manipulation leads to response discrepancy. This vulnerability is referenced as CVE-2026-23511. It is possible to launch the attack remotely. No exploit is available. Upgrading the affected component is advised.

Detailsinfo

A vulnerability, which was classified as problematic, has been found in Zitadel up to 3.4.5/4.9.0. Affected by this issue is an unknown function of the component Login Interface. The manipulation with an unknown input leads to a response discrepancy vulnerability. Using CWE to declare the problem leads to CWE-204. The product provides different responses to incoming requests in a way that reveals internal state information to an unauthorized actor outside of the intended control sphere. Impacted is confidentiality. CVE summarizes:

ZITADEL is an open source identity management platform. Prior to 4.9.1 and 3.4.6, a user enumeration vulnerability has been discovered in Zitadel's login interfaces. An unauthenticated attacker can exploit this flaw to confirm the existence of valid user accounts by iterating through usernames and userIDs. This vulnerability is fixed in 4.9.1 and 3.4.6.

The advisory is available at github.com. This vulnerability is handled as CVE-2026-23511 since 01/13/2026. The exploitation is known to be easy. The attack may be launched remotely. No form of authentication is required for exploitation. The technical details are unknown and an exploit is not available. This vulnerability is assigned to T1592 by the MITRE ATT&CK project.

Upgrading to version 3.4.6 or 4.9.1 eliminates this vulnerability.

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Productinfo

Name

Version

Website

CPE 2.3info

CPE 2.2info

CVSSv4info

VulDB Vector: 🔒
VulDB Reliability: 🔍

CVSSv3info

VulDB Meta Base Score: 5.3
VulDB Meta Temp Score: 5.2

VulDB Base Score: 5.3
VulDB Temp Score: 5.1
VulDB Vector: 🔒
VulDB Reliability: 🔍

CNA Base Score: 5.3
CNA Vector (GitHub_M): 🔒

CVSSv2info

AVACAuCIA
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VectorComplexityAuthenticationConfidentialityIntegrityAvailability
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VulDB Base Score: 🔒
VulDB Temp Score: 🔒
VulDB Reliability: 🔍

Exploitinginfo

Class: Response discrepancy
CWE: CWE-204 / CWE-203 / CWE-200
CAPEC: 🔒
ATT&CK: 🔒

Physical: No
Local: No
Remote: Yes

Availability: 🔒
Status: Not defined

EPSS Score: 🔒
EPSS Percentile: 🔒

Price Prediction: 🔍
Current Price Estimation: 🔒

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Threat Intelligenceinfo

Interest: 🔍
Active Actors: 🔍
Active APT Groups: 🔍

Countermeasuresinfo

Recommended: Upgrade
Status: 🔍

0-Day Time: 🔒

Upgrade: Zitadel 3.4.6/4.9.1

Timelineinfo

01/13/2026 CVE reserved
01/15/2026 +2 days Advisory disclosed
01/15/2026 +0 days VulDB entry created
01/15/2026 +0 days VulDB entry last update

Sourcesinfo

Product: github.com

Advisory: github.com
Status: Confirmed

CVE: CVE-2026-23511 (🔒)
GCVE (CVE): GCVE-0-2026-23511
GCVE (VulDB): GCVE-100-341390

Entryinfo

Created: 01/15/2026 20:50
Changes: 01/15/2026 20:50 (62)
Complete: 🔍
Cache ID: 216::103

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