CVE-2026-18571Network attack vector

Privilege escalation via unchecked group assignment

Published Aug 2, 2026 · Updated Aug 2, 2026

Missing authorization in the user creation API of Red Hat build of Keycloak allows remote authenticated users to assign unauthorized groups. The POST /admin/realms/{realm}/users endpoint accepts group memberships in the creation payload without checking manage-membership permission for each group. Exploitation requires non-default FGAP V2 and a high-privilege sub-administrator; newly created accounts can gain restricted data access or elevated privileges.

CVSS severity6.6
Medium
EPSS probability0.24%
Next 30 days · Sep 16, 2026
Known exploitationUnconfirmed
Based on sourced intelligence
Hinoki checkNot available
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Summary

What happened

Missing authorization in the user creation API of Red Hat build of Keycloak allows remote authenticated users to assign unauthorized groups. The POST /admin/realms/{realm}/users endpoint accepts group memberships in the creation payload without checking manage-membership permission for each group. Exploitation requires non-default FGAP V2 and a high-privilege sub-administrator; newly created accounts can gain restricted data access or elevated privileges.

The record

CVE
CVE-2026-18571
Published
Aug 2, 2026
Updated
Aug 2, 2026
Vendor
389 Directory Server
Product
Red Hat build of Keycloak
Classifications
CWE-862, T1098
Attack vector
network
Privileges
admin

Timeline

How it unfolded

  1. Aug 2, 2026CVE publishedPublication date reported by the CVE source.
  2. Aug 2, 2026Record updatedLatest update available in the CVE record.

Exploitability

Present is not the same as exploitable

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Is a vulnerable build present?

Affected versions are unavailable in this record. Check the vendor advisory for version and patch details.

What conditions does exploitation require?

Attack vectornetwork
Required privilegesadmin

What is affected?

389 Directory Server · Red Hat build of KeycloakAffected versions are unavailable in this record.

Published CVSS scores

7.2NVDCVSS:3.1/AV:N/AC:L/PR:H/UI:N/S:U/C:H/I:H/A:H
6.6Red HatCVSS:3.1/AV:N/AC:H/PR:H/UI:N/S:U/C:H/I:H/A:H

CVSS describes severity. EPSS estimates exploitation probability.

Attacks

What attackers are doing with it

Daily unique IPs observed by Shadowserver honeypots for known exploited vulnerabilities (KEVs). Missing observations do not establish an absence of attacks.

Daily unique IPsNo honeypot observations are available for this CVE in the selected window.

No observations available

Sep 10, 2026Sep 16, 2026
Latest reporting daySep 16, 2026
Latest daily unique IPsUnavailable
Prior 30-day averageUnavailable
SourceShadowserver honeypots (KEV)
Vectornetwork
Privilegesadmin
Known exploitationUnconfirmed
Public exploitUnconfirmed

Weakness, pattern, technique

CWE-862Missing Authorization
T1098Account Manipulation

Public exploit references

No public exploit references are available in this record.

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Technologies

Your stack

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Your stack

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