CVE-2026-16100CWE-770denial-of-service

CVE-2026-16100

Medium · published August 5, 2026

CVSS v3.1
6.5
EPSS
1%
Percentile
45.3
In the wild
Unconfirmed
What it is

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.

The record
Technical detail
CVSS v3.1
6.5 · MEDIUM
Vector
CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H
CVSS v4.0
Not supplied
EPSS
0.00552 · 45.3th percentile
Weakness
CWE-770 · Allocation of Resources Without Limits or Throttling
Published
2026-08-05T19:16Z
Affected products (1)
ProductVersionsFixed in
redhat/build_of_keycloak≥ 26.6, < 26.6.526.6.5
References (4)
https://access.redhat.com/errata/RHSA-2026:50848 · [email protected]https://access.redhat.com/errata/RHSA-2026:50849 · [email protected]https://access.redhat.com/security/cve/CVE-2026-16100 · [email protected]https://bugzilla.redhat.com/show_bug.cgi?id=2501730 · [email protected]
EPSS history
Timeline
  • 05 AUG 13:50Z
    Keycloak-services: keycloak-services: unbounded metric cardinality in user event metrics via request-controlled error text
    cvelistv5