How severe is CVE-2026-23511?

CVE-2026-23511 has a CVSS 3.x base score of 5.3, rated medium severity. It is exploitable over network with low attack complexity, requires no privileges and no user interaction. Impact on confidentiality is low, integrity none, and availability none.

Is CVE-2026-23511 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 0% (28th percentile), an estimate of the probability of exploitation in the next 30 days.

What products are affected by CVE-2026-23511?

CVE-2026-23511 affects Zitadel. See the affected-products list for the exact vulnerable versions.

How do I fix CVE-2026-23511?

Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround.

Does CVE-2026-23511 have an EU (EUVD) identifier?

Yes. CVE-2026-23511 is tracked in the ENISA EU Vulnerability Database (EUVD) as EUVD-2026-2788.

When was CVE-2026-23511 published?

CVE-2026-23511 was published on 2026-01-15 and last updated on 2026-06-17.

CVE-2026-23511

CVE-2026-23511 is a medium-severity vulnerability in Zitadel with a CVSS 3.x base score of 5.3. It is not currently listed as actively exploited by CISA, and its EPSS exploit-prediction score is low. The underlying weakness is classified as CWE-204.

Key facts

Severity: Medium (CVSS 3.x base score 5.3)
EPSS exploit prediction: 0% (28th percentile)
Actively exploited: Not listed in CISA KEV
EU (EUVD) id: EUVD-2026-2788
Weakness: CWE-204
Affected product: Zitadel
Published: 2026-01-15
Last modified: 2026-06-17

Description

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.

Frequently asked questions

What is CVE-2026-23511?: 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.
How severe is CVE-2026-23511?: CVE-2026-23511 has a CVSS 3.x base score of 5.3, rated medium severity. It is exploitable over network with low attack complexity, requires no privileges and no user interaction. Impact on confidentiality is low, integrity none, and availability none.
Is CVE-2026-23511 being actively exploited?: It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 0% (28th percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2026-23511?: CVE-2026-23511 affects Zitadel. See the affected-products list for the exact vulnerable versions.
How do I fix CVE-2026-23511?: Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround.
Does CVE-2026-23511 have an EU (EUVD) identifier?: Yes. CVE-2026-23511 is tracked in the ENISA EU Vulnerability Database (EUVD) as EUVD-2026-2788.
When was CVE-2026-23511 published?: CVE-2026-23511 was published on 2026-01-15 and last updated on 2026-06-17.

References

Affected products (1)

cpe:2.3:a:zitadel:zitadel:*:*:*:*:*:*:*:*

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