How severe is CVE-2026-4633?

CVE-2026-4633 has a CVSS 3.x base score of 3.7, rated low severity. It is exploitable over network with high attack complexity, requires no privileges and no user interaction. Impact on confidentiality is low, integrity none, and availability none.

Is CVE-2026-4633 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 0% (24th percentile), an estimate of the probability of exploitation in the next 30 days.

What products are affected by CVE-2026-4633?

CVE-2026-4633 affects Redhat Build Of Keycloak. See the affected-products list for the exact vulnerable versions.

How do I fix CVE-2026-4633?

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

Does CVE-2026-4633 have an EU (EUVD) identifier?

Yes. CVE-2026-4633 is tracked in the ENISA EU Vulnerability Database (EUVD) as EUVD-2026-14400.

When was CVE-2026-4633 published?

CVE-2026-4633 was published on 2026-03-23 and last updated on 2026-06-17.

CVE-2026-4633

CVE-2026-4633 is a low-severity vulnerability in Redhat Build Of Keycloak with a CVSS 3.x base score of 3.7. 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-209.

Key facts

Severity: Low (CVSS 3.x base score 3.7)
EPSS exploit prediction: 0% (24th percentile)
Actively exploited: Not listed in CISA KEV
EU (EUVD) id: EUVD-2026-14400
Weakness: CWE-209
Affected product: Redhat Build Of Keycloak
Published: 2026-03-23
Last modified: 2026-06-17

Description

A flaw was found in Keycloak. A remote attacker can exploit differential error messages during the identity-first login flow when Organizations are enabled. This vulnerability allows an attacker to determine the existence of users, leading to information disclosure through user enumeration.

Frequently asked questions

What is CVE-2026-4633?: A flaw was found in Keycloak. A remote attacker can exploit differential error messages during the identity-first login flow when Organizations are enabled. This vulnerability allows an attacker to determine the existence of users, leading to information disclosure through user enumeration.
How severe is CVE-2026-4633?: CVE-2026-4633 has a CVSS 3.x base score of 3.7, rated low severity. It is exploitable over network with high attack complexity, requires no privileges and no user interaction. Impact on confidentiality is low, integrity none, and availability none.
Is CVE-2026-4633 being actively exploited?: It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 0% (24th percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2026-4633?: CVE-2026-4633 affects Redhat Build Of Keycloak. See the affected-products list for the exact vulnerable versions.
How do I fix CVE-2026-4633?: Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround.
Does CVE-2026-4633 have an EU (EUVD) identifier?: Yes. CVE-2026-4633 is tracked in the ENISA EU Vulnerability Database (EUVD) as EUVD-2026-14400.
When was CVE-2026-4633 published?: CVE-2026-4633 was published on 2026-03-23 and last updated on 2026-06-17.

References

Affected products (1)

cpe:2.3:a:redhat:build_of_keycloak:-:*:*:*:-:*:*:*

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