Medium severity · published Mar 23, 2026
CVE-2026-4628
Keycloak: org.keycloak.authorization: keycloak: unauthorized resource modification due to improper access control
4.3
CVSS
0.3%
EPSS
No
On KEV
Description
A flaw was found in Keycloak. An improper Access Control vulnerability in Keycloak’s User-Managed Access (UMA) resource_set endpoint allows attackers with valid credentials to bypass the allowRemoteResourceManagement=false restriction. This occurs due to incomplete enforcement of access control checks on PUT operations to the resource_set endpoint. This issue enables unauthorized modification of protected resources, impacting data integrity.
CVSS vector
CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:N/I:L/A:N
Attack vector
Network
Complexity
Low
Privileges
Low
User interaction
None
Confidentiality
None
Integrity
Low
Availability
None
Scope
Unchanged
Exploitation
Is it being used?
Exploit prediction (EPSS)0.3% · higher than 18% of CVEs
Exploited in the wildNo evidence yet
CISA KEVNot listed
Ransomware campaign useNot known
Affected products
Which versions
RH
Red Hat Build of Keycloak · Red Hat
All versions, or not specified · source: vendor
BO
Build OF Keycloak · Redhat
All versions, or not specified · source: NVD
References
NVD
https://nvd.nist.gov/vuln/detail/CVE-2026-4628
CVE.org
https://www.cve.org/CVERecord?id=CVE-2026-4628
access.redhat.com
https://access.redhat.com/errata/RHSA-2026:19596
Vendor Advisory
https://access.redhat.com/security/cve/CVE-2026-4628
Issue Tracking
https://bugzilla.redhat.com/show_bug.cgi?id=2450240
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