CVE-2026-9801
A flaw was found in Keycloak. A remote attacker with high privileges, such as a realm administrator configuring a malicious Lightweight Directory Access Protocol (LDAP) server or an attacker compromising an upstream LDAP server, could exploit this vulnerability. By sending a malformed LDAP password policy response during a password authentication request, the attacker can trigger an OutOfMemoryError. This causes the Keycloak Java Virtual Machine (JVM) to terminate, leading to a denial of service (DoS) for all realms on the affected node.
Published:May 28, 2026
Last Modified:Jun 26, 2026
EPS:May 28, 2026
EPSS Score:0.00442
CVSS Score:4.9
Affected Products
Vendor
Product
Action
Vendor
Redhat
Product
Build Keycloak
Redhat
Build Keycloak
Vendor
Redhat
Product
Build Of Keycloak
Redhat
Build Of Keycloak
Exploits
No exploit reference
Common Weakness Enumeration
Common Attack Pattern Enumeration and Classification (CAPEC)
No CAPEC recorded yet
Related CVEs
References
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
