CVE-2026-107889
A flaw was found in the login theme rendering component of Keycloak. The issue occurs because the security filter responsible for cleaning user input can be bypassed, allowing a realm administrator to store malicious scripts in display fields. This could result in unauthorized JavaScript execution in the browsers of users visiting the login page, potentially leading to data exposure or session interference.
Published:Oct 8, 2026
Last Modified:Oct 26, 2026
EPS:Oct 9, 2026
EPSS Score:0.00268
CVSS Score:5.5
Affected Products
Vendor
Product
Action
Vendor
Redhat
Product
Build Keycloak
Redhat
Build Keycloak
Vendor
Redhat
Product
Build Of Keycloak
Redhat
Build Of Keycloak
Vendor
Redhat
Product
Red Hat Single Sign On
Redhat
Red Hat Single Sign On
Vendor
Redhat
Product
Single Sign-on
Redhat
Single Sign-on
Exploits
No exploit reference
Common Weakness Enumeration
Common Attack Pattern Enumeration and Classification (CAPEC)
Related CVEs
Common Vulnerability Scoring System
Attack Vector
Network
Adjacent
Local
Physical
Privileges Required
None
Low
High
User Interaction
None
Required
Scope
Unchanged
Changed
Confidentiality
None
Low
High
Integrity
None
Low
High
Availability
None
Low
High
