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Vulnerability record · CVE-2026-16100 · published 5 August 2026

CVE-2026-16100: Redhat build of keycloak allocation without limits vulnerability

Redhat · Build Of Keycloak

A flaw was found in the user-event metrics recording of Keycloak. When metrics are enabled, the system records raw error messages from failed account operations as Prometheus metric labels. Because these error messages can include user-supplied input like nonexistent client IDs, an authenticated user can create a massive number of unique metric entries, eventually exhausting system memory and causing the service to crash or become unavailable.

6.5 CVSS 3.1 Medium EPSS 0.55% · top 56.0% CWE-770 · Allocation without limits
6.5CVSS 3.1 base score
0.55%EPSS exploitation probability, 30 days
NoNot in CISA KEV
1Affected product versions listed by NVD
4References
31 Aug 2026Last modified by NVD

Description

A flaw was found in the user-event metrics recording of Keycloak. When metrics are enabled, the system records raw error messages from failed account operations as Prometheus metric labels. Because these error messages can include user-supplied input like nonexistent client IDs, an authenticated user can create a massive number of unique metric entries, eventually exhausting system memory and causing the service to crash or become unavailable.

CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H

Affected products

1 vulnerable configurations from NVD's CPE data, grouped by vendor and product.

References

LinkTags
https://access.redhat.com/errata/RHSA-2026:50848 Vendor Advisory
https://access.redhat.com/errata/RHSA-2026:50849 Vendor Advisory
https://access.redhat.com/security/cve/CVE-2026-16100 Vendor Advisory
https://bugzilla.redhat.com/show_bug.cgi?id=2501730 Issue TrackingVendor Advisory

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Related vulnerabilities

Same products first, then exploited flaws of the same weakness class.

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Source: NIST National Vulnerability Database (record CVE-2026-16100), CISA KEV, FIRST EPSS (scores of 2026-09-30). This page is refreshed as NVD updates the record.