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.
CVE-2026-16100
Score 6.5 from GitHub Security Advisory published 2026-08-05. a secondary CVSS source baseline 6.5; sources differ by 0.0.
- Lower severity and no public exploit yet
A fix is available — apply it.
- CVSS v3
- 6.5
- EG Score
- 6.5(high)
- EG Risk
- 29(Track)EG Risk 29/100SSVC: Track
EG Risk is EchelonGraph's 0–100 priority score: it fuses intrinsic severity with real-world exploitation and automatability so you can rank equal-severity CVEs and fix the most dangerous first. Higher = act sooner. Distinct from the 0–10 EG Score (severity).
How it’s computedSeverity65% × 45%Exploitation0% × 40%Automatability0% × 15%Action: Routine — remediate on your standard cadence. - EPSS PROB
- 0%
- EPSS %ILE
- 23%
- KEV
- Not listed
Published
August 5, 2026
Last Modified
August 10, 2026
Advisory Details (2)
Auto-updated Aug 5, 20262501730 – (CVE-2026-16100) CVE-2026-16100 keycloak-services: keycloak-services: Unbounded metric cardinality in user event metrics via request-controlled error text
https://bugzilla.redhat.com/show_bug.cgi?id=2501730CVE-2026-16100 - Red Hat Customer Portal
Affected: Red Hat Enterprise Linux 8 or OpenShift Container Platform 4, is affected by this vulnerability and a fix may be released to a
https://access.redhat.com/security/cve/CVE-2026-16100Vendor Advisories for CVE-2026-16100(3)
These vendors published their own advisory mentioning this CVE — often with vendor-specific remediation steps + affected product lists not in NVD.
- RHSA-2026:50849Red Hat Product SecurityHigh
Red Hat Security Advisory: Red Hat build of Keycloak 26.6.5 Images Security Update
- RHSA-2026:50848Red Hat Product SecurityHigh
Red Hat Security Advisory: Red Hat build of Keycloak 26.6.5 Security Update
- GHSA-xj3w-m54w-h7p9GitHub Security AdvisoriesMedium
A flaw was found in the user-event metrics recording of Keycloak. When metrics are enabled, the...
Patch Availability(2)
| Vendor / Ecosystem | Fixed in / Patch | Released | Source |
|---|---|---|---|
| redhat | rhbk/keycloak-rhel9-operator:26.6-11 | 2026-08-05 | redhat |
| redhat | rhbk-openshift-rhel9/rhbk-openshift-rhel9 | 2026-08-05 | redhat |
Patches are aggregated from vendor advisories (Red Hat, Microsoft, Cisco, GitHub) and package ecosystems (OSV, GHSA). Multiple rows for the same upstream release have been deduplicated.
Weakness Classification(1)
MITRE Common Weakness Enumeration — the root-cause categories this CVE belongs to.
Data Freshness Timeline
(refreshed 30× in last 7d / 73× in last 30d)
Each row is a source pipeline that fetched or updated this CVE on that date, with what changed. For example, "NVD update" means NVD published or revised its analysis for this CVE; "MITRE cvelistV5" means we ingested or refreshed it from the CNA feed. Most recent first.
- 2026-08-20 22:55 UTCEPSS rescore
- 2026-08-20 22:19 UTCVendor advisory
- 2026-08-20 22:19 UTCGHSA enrichment
- 2026-08-20 00:11 UTCEG score recompute
- 2026-08-20 00:11 UTCVendor advisory
- 2026-08-20 00:11 UTCGHSA enrichment
- 2026-08-19 17:03 UTCEPSS rescore
- 2026-08-19 02:02 UTCEG score recompute
- 2026-08-19 02:02 UTCVendor advisory
- 2026-08-19 02:02 UTCGHSA enrichment
- 2026-08-18 13:48 UTCEPSS rescore
- 2026-08-18 03:53 UTCEG score recompute
- 2026-08-18 03:53 UTCVendor advisory
- 2026-08-18 03:53 UTCGHSA enrichment
- 2026-08-17 13:47 UTCEPSS rescore
- 2026-08-17 05:45 UTCEG score recompute
- 2026-08-17 05:45 UTCVendor advisory
- 2026-08-17 05:45 UTCGHSA enrichment
- 2026-08-16 14:56 UTCEPSS rescore
- 2026-08-16 07:15 UTCEG score recompute
- 2026-08-16 07:15 UTCVendor advisory
- 2026-08-16 07:15 UTCGHSA enrichment
- 2026-08-16 02:14 UTCEPSS rescore
- 2026-08-15 09:07 UTCEG score recompute
- 2026-08-15 09:07 UTCVendor advisory
Show 48 moreShow fewer
- 2026-08-15 09:07 UTCGHSA enrichment
- 2026-08-15 01:30 UTCEPSS rescore
- 2026-08-14 10:58 UTCEG score recompute
- 2026-08-14 10:58 UTCVendor advisory
- 2026-08-14 10:58 UTCGHSA enrichment
- 2026-08-13 22:00 UTCEPSS rescore
- 2026-08-13 12:50 UTCVendor advisory
- 2026-08-13 12:50 UTCGHSA enrichment
- 2026-08-12 14:42 UTCEG score recompute
- 2026-08-12 14:42 UTCVendor advisory
- 2026-08-12 14:42 UTCGHSA enrichment
- 2026-08-12 13:50 UTCEPSS rescore
- 2026-08-11 16:34 UTCEG score recompute
- 2026-08-11 16:34 UTCVendor advisory
- 2026-08-11 16:34 UTCGHSA enrichment
- 2026-08-11 13:42 UTCEPSS rescore
- 2026-08-11 00:00 UTCEPSS rescore
- 2026-08-10 18:26 UTCVendor advisory
- 2026-08-10 18:26 UTCGHSA enrichment
- 2026-08-10 08:22 UTCEG score recompute
- 2026-08-10 08:22 UTCVendor advisory
- 2026-08-10 08:22 UTCGHSA enrichment
- 2026-08-09 13:46 UTCEPSS rescore
- 2026-08-09 10:14 UTCEG score recompute
- 2026-08-09 10:14 UTCVendor advisory
- 2026-08-09 10:14 UTCGHSA enrichment
- 2026-08-08 16:37 UTCEPSS rescore
- 2026-08-08 12:06 UTCEG score recompute
- 2026-08-08 12:06 UTCVendor advisory
- 2026-08-08 12:06 UTCGHSA enrichment
- 2026-08-07 13:57 UTCVendor advisory
- 2026-08-07 13:57 UTCGHSA enrichment
- 2026-08-06 15:49 UTCEG score recompute
- 2026-08-06 15:49 UTCVendor advisory
- 2026-08-06 15:49 UTCGHSA enrichment
- 2026-08-06 13:46 UTCEPSS rescore
- 2026-08-05 19:31 UTCGHSA enrichment
- 2026-08-05 18:32 UTCEG score recompute
- 2026-08-05 18:32 UTCGHSA enrichment
- 2026-08-05 17:57 UTCEG score recompute
- 2026-08-05 17:57 UTCGHSA enrichment
- 2026-08-05 17:30 UTCEG score recompute
- 2026-08-05 17:30 UTCGHSA enrichment
- 2026-08-05 16:54 UTCEG score recompute
- 2026-08-05 16:54 UTCGHSA enrichment
- 2026-08-05 15:27 UTCEG score recompute
- 2026-08-05 14:36 UTCEG score recompute
- 2026-08-05 14:35 UTCMITRE cvelistV5first tracked
Frequently asked(5)
What is CVE-2026-16100?
When was CVE-2026-16100 disclosed?
Is CVE-2026-16100 actively exploited?
What is the CVSS score of CVE-2026-16100?
How do I remediate CVE-2026-16100?
Dependency Blast Radius
Explore the affected products and dependency analysis for CVE-2026-16100
Is Your Infrastructure Affected by CVE-2026-16100?
EchelonGraph automatically scans your cloud infrastructure and maps CVE exposure using blast radius analysis.