Keycloak-services: keycloak-services: default dcr policy allows role forgery via user property mappers

Summary

CVE	CVE-2026-16102
State	PUBLISHED
Assigner	redhat
Source Priority	CVE Program / NVD first with legacy fallback
Published	2026-08-05 15:16:37 UTC
Updated	2026-08-05 19:17:25 UTC
Description	A flaw was found in the Dynamic Client Registration (DCR) component of Keycloak, an identity and access management solution. The default DCR policy fails to properly validate the claim path for User Property mappers, allowing them to write values to sensitive internal claim locations. An attacker with a standard user account and a limited Initial Access Token can exploit this to forge administrative roles in their access token. This allows the attacker to take over other clients, steal confidential secrets, and potentially gain full administrative control over the realm.

Risk And Classification

Primary CVSS: v3.1 8.1 HIGH from [email protected]

CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:N

Problem Types: CWE-284 | CWE-284 CWE-284 Improper Access Control

Version	Source	Type	Score	Severity	Vector
3.1	[email protected]	Secondary	8.1	HIGH	`CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:N`
3.1	CNA	CVSS	8.1	HIGH	`CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:N`

CVSS v3.1 Breakdown

Attack Vector

Network

Attack Complexity

Low

Privileges Required

Low

User Interaction

None

Scope

Unchanged

Confidentiality

High

Integrity

High

Availability

None

CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:N

Vendor Declared Affected Products

Source	Vendor	Product	Version	Platforms
CNA	Red Hat	Red Hat Build Of Keycloak 26.4	unaffected 26.4.14-1 * rpm	Not specified
CNA	Red Hat	Red Hat Build Of Keycloak 26.4	unaffected 26.4-22 * rpm	Not specified
CNA	Red Hat	Red Hat Build Of Keycloak 26.4	unaffected 26.4-22 * rpm	Not specified
CNA	Red Hat	Red Hat Build Of Keycloak 26.4.14	Not specified	Not specified
CNA	Red Hat	Red Hat Build Of Keycloak 26.4.14	Not specified	Not specified
CNA	Red Hat	Red Hat Build Of Keycloak 26.6	unaffected 26.6.5-1 * rpm	Not specified
CNA	Red Hat	Red Hat Build Of Keycloak 26.6	unaffected 26.6-11 * rpm	Not specified
CNA	Red Hat	Red Hat Build Of Keycloak 26.6	unaffected 26.6-11 * rpm	Not specified
CNA	Red Hat	Red Hat Build Of Keycloak 26.6.5	Not specified	Not specified
CNA	Red Hat	Red Hat Build Of Keycloak 26.6.5	Not specified	Not specified
CNA	Red Hat	Red Hat Build Of Keycloak 26.6.5	Not specified	Not specified
CNA	Red Hat	Red Hat Data Grid 8	Not specified	Not specified
CNA	Red Hat	Red Hat JBoss Enterprise Application Platform Expansion Pack	Not specified	Not specified
CNA	Red Hat	Red Hat Single Sign-On 7	Not specified	Not specified

References

Reference	Source	Link	Tags
access.redhat.com/errata/RHSA-2026:50846	[email protected]	access.redhat.com
access.redhat.com/errata/RHSA-2026:50847	[email protected]	access.redhat.com
access.redhat.com/errata/RHSA-2026:50848	[email protected]	access.redhat.com
access.redhat.com/errata/RHSA-2026:50849	[email protected]	access.redhat.com
access.redhat.com/security/cve/CVE-2026-16102	[email protected]	access.redhat.com
bugzilla.redhat.com/show_bug.cgi	[email protected]	bugzilla.redhat.com
CVE Program record	CVE.ORG	www.cve.org	canonical
NVD vulnerability detail	NVD	nvd.nist.gov	canonical, analysis

Vendor Comments And Credit

Discovery Credit

CNA: Red Hat would like to thank yd1ng for reporting this issue. (en)

Additional Advisory Data

Source	Time	Event
CNA	2026-07-15T12:14:36.000Z	Reported to Red Hat.
CNA	2026-08-05T02:02:00.000Z	Made public.

Workarounds

CNA: 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.

There are currently no legacy QID mappings associated with this CVE.