redhat build-keycloak CVE-2026-101333 vulnerability in Red Hat Products
Published on September 28, 2026

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

Vendor Advisory NVD

Vulnerability Analysis

CVE-2026-101333 can be exploited with network access, and does not require authorization privileges or user interaction. This vulnerability is consided to have a high level of attack complexity. The potential impact of an exploit of this vulnerability is considered to have no impact on confidentiality and integrity, and a small impact on availability.

Exploitation:
NONE
Automatable:
NO
Technical Impact:
PARTIAL
Attack Vector:
NETWORK
Attack Complexity:
HIGH
Privileges Required:
NONE
User Interaction:
NONE
Scope:
UNCHANGED
Confidentiality Impact:
NONE
Integrity Impact:
NONE
Availability Impact:
LOW

Timeline

Reported to Red Hat.

Made public.

Weakness Type

Allocation of Resources Without Limits or Throttling

The software allocates a reusable resource or group of resources on behalf of an actor without imposing any restrictions on the size or number of resources that can be allocated, in violation of the intended security policy for that actor.


Products Associated with CVE-2026-101333

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Affected Versions

Red Hat build of Keycloak 26.6.8: Red Hat build of Keycloak 26.6.8: Red Hat Single Sign-On 7: