CVE-2026-16100Keycloak-services: keycloak-services: unbounded metric cardinality in user event metrics via request-controlled error text
Updated under an hour ago ()
Does this affect you?
It affects Red Hat build of Keycloak 26.6 and 4 other products. Add what you run to find out whether that includes you.
No exploitation reported and no EPSS estimate yet.
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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
- 6.5 MEDIUM (v3.1, CNA)CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H
- Weakness (CWE)
- CWE-770
- Known exploited
- Not in CISA's KEV catalog
- EPSS (exploitation in the next 30 days)
- Not loaded for this CVE
- Assigned by
- redhat
- NVD analysis
- Modified
- Record last updated
- Aug 31, 2026
- First seen by InfoSec Signals
- Oct 9, 2026
Affected products
Red Hat Red Hat build of Keycloak 26.6 redhat:build_keycloak | from 26.6.5-1 not affected | CNA record |
Red Hat Red Hat Data Grid 8 redhat:jboss_data_grid | 8 | CNA record |
Red Hat Red Hat JBoss Enterprise Application Platform Expansion Pack redhat:jbosseapxp | Versions not stated | CNA record |
Red Hat Red Hat Single Sign-On 7 redhat:red_hat_single_sign_on | 7 | CNA record |
redhat build_of_keycloak redhat:build_of_keycloak | from 26.6 before 26.6.5 | NVD |
References
- https://access.redhat.com/errata/RHSA-2026:50848vendor-advisory, x-refsource-redhat
- https://access.redhat.com/errata/RHSA-2026:50849vendor-advisory, x-refsource-redhat
- https://access.redhat.com/security/cve/CVE-2026-16100vdb-entry, x-refsource-redhat, vendor-advisory
- https://bugzilla.redhat.com/show_bug.cgi?id=2501730issue-tracking, x-refsource-redhat, vendor-advisory
The CVE record on cve.org NVD's entry
The CVE record is authoritative. Products marked “from the name” were identified from the CNA's free-text names, not a CPE, and are matched less certainly. This product uses the NVD API but is not endorsed or certified by the NVD.