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Red HatCVE-2026-16100

Red Hat user-event metrics recording of Keycloak.: resource exhaustion

Medium6.5CVE-2026-16100 · Published Aug 5, 2026 · updated Aug 31, 2026

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.

Red Hat advisory

Affected versions

PackageAffectedFixed in
Red Hat Data Grid 8
Product
all versionsNo fix yet
Red Hat JBoss Enterprise Application Platform Expansion Pack
Product
all versionsNo fix yet
Red Hat Single Sign-On 7
Product
all versionsNo fix yet
Red Hat build of Keycloak 26.6.5
Product
all versionsNo fix yet
all versionsNo fix yet
all versionsNo fix yet
Details and references

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