Sources: National Vulnerability Database, CVE.org, CISA KEV, FIRST EPSS
CVE-2026-120984 Overview
A flaw was found in the Keycloak server's client management component. When a client is created or imported with authorization services enabled, the system fails to properly clear an internal session attribute used during the setup process. This allows an authenticated attacker with client management permissions to bypass security controls and upload a malicious JavaScript policy, which is then executed on the server when an authorization request is made. Successful exploitation could allow the attacker to run arbitrary code on the server, potentially compromising the entire system.
Critical Impact
Affected Products
- Red Hat Keycloak server's client management component: see the vendor advisory for the exact affected versions
Discovery Timeline
- 2026-11-07: CVE-2026-120984 published to the National Vulnerability Database by secalert@redhat.com
- 2026-11-07: last updated in the NVD database
Technical Details for CVE-2026-120984
Vulnerability Analysis
CVE-2026-120984 is a Code Injection weakness (CWE-94: Code Injection) in Red Hat Keycloak server's client management component. Based on its CVSS vector, the flaw can be reached over the network, needs some level of access, and needs no user interaction. Attacker input is executed as program code.
With a CVSS base score of 9.1, apply the vendor fix and confirm exposure on internet facing and business critical assets first.
Root Cause
The weakness is classified as CWE-94: Code Injection. Attacker input is executed as program code.
Attack Vector
Based on the CVSS vector, the flaw can be reached over the network, needs some level of access, and needs no user interaction. Attack complexity is low complexity.
No exploitation in the wild is confirmed by CISA at the time of the last update. Check the references below for any vendor or researcher proof of concept.
CVSS:3.1/AV:N/AC:L/PR:H/UI:N/S:C/C:H/I:H/A:H
Detection Methods for CVE-2026-120984
Detection Strategies
- Inventory every instance of Red Hat Keycloak server's client management component and compare the running version with the affected range above.
- Check external attack surface scans for internet facing instances of the component.
- Run an authenticated vulnerability scan once your scanner ships a check for this CVE.
Monitoring Recommendations
- Forward Red Hat Keycloak server's client management component application, access and audit logs to your SIEM for retrospective hunting.
- Alert on new processes, configuration changes or outbound connections from the affected service.
- Track the vendor advisory and the CISA KEV catalog for changes in exploitation status.
How to Mitigate CVE-2026-120984
Immediate Actions Required
- Apply the fixed version of Red Hat Keycloak server's client management component named in the vendor advisory.
- Prioritize internet facing and business critical instances first.
- Rescan after the change to confirm the exposure is closed.
Patch Information
Use the fixed version listed in the vendor advisory for Red Hat Keycloak server's client management component.
Workarounds
- If patching must wait, restrict network access to the affected service and place it behind authentication or a web application firewall rule.
CWE References
- CWE-94: Code Injection More CVEs with this weakness
Technical References
This entry is built directly from NVD, CISA KEV and EPSS data. Verify fixed versions in the vendor advisory before you deploy.
Frequently asked questions
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