CVE-2026-101333

Keycloak-services: keycloak-services: unbounded metric series creation via idp tag on broker login endpoint

Published Sep 28, 2026 CVSS 3.1 · 3.7 Low EPSS < 1% KEV · Not listed
Description
A flaw was found in the Micrometer user-event metrics listener of Keycloak, a solution for integrated identity and access management. The issue occurs when the listener is configured to include the idp tag. An unauthenticated attacker can send requests to the identity broker login endpoint using arbitrary provider aliases, causing the system to create an unlimited number of metric time series. This can lead to excessive memory consumption and degrade the performance of both the server and its monitoring tools.

Remediation

Vendor Workaround

Mitigation for this issue is either not available or the currently available options do not meet the Red Hat Product Security criteria comprising ease of use and deployment, applicability to widespread installation base, or stability.

Tracking

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Advisories

No advisories available
History
Type Values Removed Values Added
CPEs cpe:/a:redhat:build_keycloak: cpe:/a:redhat:build_keycloak:26.6::el9
References
Type Values Removed Values Added
First Time appeared Redhat build Of Keycloak
Redhat single Sign-on
Vendors & Products Redhat build Of Keycloak
Redhat single Sign-on
Type Values Removed Values Added
Metrics ssvc

{'options': {'Automatable': 'no', 'Exploitation': 'none', 'Technical Impact': 'partial'}, 'version': '2.0.3'}

Type Values Removed Values Added
Description A flaw was found in the Micrometer user-event metrics listener of Keycloak, a solution for integrated identity and access management. The issue occurs when the listener is configured to include the idp tag. An unauthenticated attacker can send requests to the identity broker login endpoint using arbitrary provider aliases, causing the system to create an unlimited number of metric time series. This can lead to excessive memory consumption and degrade the performance of both the server and its monitoring tools.
Title Keycloak-services: keycloak-services: unbounded metric series creation via idp tag on broker login endpoint
First Time appeared Redhat
Redhat build Keycloak
Redhat red Hat Single Sign On
Weaknesses CWE-770
CPEs cpe:/a:redhat:build_keycloak:
cpe:/a:redhat:red_hat_single_sign_on:7
Vendors & Products Redhat
Redhat build Keycloak
Redhat red Hat Single Sign On
References
Metrics cvssV3_1

{'score': 3.7, 'vector': 'CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:N/I:N/A:L'}

Weaknesses

Sources

Status
PUBLISHED
Assigner
redhat
Published
Updated
Nov 6, 2026, 10:28 AM
Reserved
Sep 28, 2026, 2:09 PM
Status
Awaiting Analysis
Published
Sep 28, 2026, 3:17 PM
Modified
Nov 6, 2026, 11:17 AM
Severity
Moderate
Public date
Sep 25, 2026, 8:30 AM