CVE-2026-16100

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 v3 6.5 MEDIUM

6.5^/10

CVSS v3 : MEDIUM

Vector :

Exploitability : 2.8 / Impact : 3.6

Attack Vector NETWORK

Attack Complexity LOW

Privileges Required LOW

User Interaction NONE

Confidentiality Impact NONE

Integrity Impact NONE

Availability Impact HIGH

Scope UNCHANGED

References

Link	Resource
https://access.redhat.com/errata/RHSA-2026:50848	Vendor Advisory
https://access.redhat.com/errata/RHSA-2026:50849	Vendor Advisory
https://access.redhat.com/security/cve/CVE-2026-16100	Vendor Advisory
https://bugzilla.redhat.com/show_bug.cgi?id=2501730	Issue Tracking Vendor Advisory

Configurations

Configuration 1 (hide)

cpe:2.3:a:redhat:build_of_keycloak:*:*:*:*:*:*:*:*

History

No history.

Information

Published : 2026-08-05 15:16

Updated : 2026-08-31 12:17

NVD link : CVE-2026-16100

Mitre link : CVE-2026-16100

CVE.ORG link : CVE-2026-16100

JSON object : View

Products Affected

redhat

build_of_keycloak

CWE

CWE-770

Allocation of Resources Without Limits or Throttling

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