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.
Affected products
redhat: build of keycloak
References4
- access.redhat.com/errata/RHSA-2026:50848 Vendor Advisory
- access.redhat.com/errata/RHSA-2026:50849 Vendor Advisory
- access.redhat.com/security/cve/CVE-2026-16100 Vendor Advisory
- bugzilla.redhat.com/show_bug.cgi?id=2501730 Issue TrackingVendor Advisory
Metrics
- CVSS 3.1
-
6.5
MEDIUM
Score source: CNA
CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H - EPSS — exploit probability
- 1% percentile: 47 · as of 13 November 2026
- CWE
- CWE-770
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