CVE-2026-2575
March 18, 2026
A flaw was found in Keycloak. An unauthenticated remote attacker can trigger an application level Denial of Service (DoS) by sending a highly compressed SAMLRequest through the SAML Redirect Binding. The server fails to enforce size limits during DEFLATE decompression, leading to an OutOfMemoryError (OOM) and subsequent process termination. This vulnerability allows an attacker to disrupt the availability of the service.
Affected Packages
https://github.com/keycloak/keycloak.git (GITHUB):
Affected version(s) >=1.0-alpha-1 <26.4.10Fix Suggestion:
Update to version 26.4.10https://github.com/keycloak/keycloak.git (GITHUB):
Affected version(s) >=26.5.0 <26.5.4Fix Suggestion:
Update to version 26.5.4org.keycloak:keycloak-saml-core (JAVA):
Affected version(s) >=1.1.0.Beta1 <26.5.4Fix Suggestion:
Update to version 26.5.4org.keycloak:keycloak-services (JAVA):
Affected version(s) >=26.5.0 <26.5.4Fix Suggestion:
Update to version 26.5.4org.keycloak:keycloak-saml-core (JAVA):
Affected version(s) >=26.5.0 <26.5.4Fix Suggestion:
Update to version 26.5.4org.keycloak:keycloak-saml-adapter-core (JAVA):
Affected version(s) >=1.6.0.Final <26.5.4Fix Suggestion:
Update to version 26.5.4org.keycloak:keycloak-services (JAVA):
Affected version(s) >=1.0-alpha-1 <26.5.4Fix Suggestion:
Update to version 26.5.4org.keycloak:keycloak-saml-adapter-core (JAVA):
Affected version(s) >=26.5.0 <26.5.4Fix Suggestion:
Update to version 26.5.4Related Resources (8)
Do you need more information?
Contact UsCVSS v4
Base Score:
6.9
Attack Vector
NETWORK
Attack Complexity
LOW
Attack Requirements
NONE
Privileges Required
NONE
User Interaction
NONE
Vulnerable System Confidentiality
NONE
Vulnerable System Integrity
NONE
Vulnerable System Availability
LOW
Subsequent System Confidentiality
NONE
Subsequent System Integrity
NONE
Subsequent System Availability
NONE
CVSS v3
Base Score:
5.3
Attack Vector
NETWORK
Attack Complexity
LOW
Privileges Required
NONE
User Interaction
NONE
Scope
UNCHANGED
Confidentiality
NONE
Integrity
NONE
Availability
LOW
Weakness Type (CWE)
Improper Handling of Highly Compressed Data (Data Amplification)
EPSS
Base Score:
0.03
