diff --git a/oauth2-authorization-server/src/main/java/org/springframework/security/oauth2/server/authorization/authentication/OAuth2DeviceAuthorizationRequestAuthenticationToken.java b/oauth2-authorization-server/src/main/java/org/springframework/security/oauth2/server/authorization/authentication/OAuth2DeviceAuthorizationRequestAuthenticationToken.java
index 883b4a97a..9bc965f38 100644
--- a/oauth2-authorization-server/src/main/java/org/springframework/security/oauth2/server/authorization/authentication/OAuth2DeviceAuthorizationRequestAuthenticationToken.java
+++ b/oauth2-authorization-server/src/main/java/org/springframework/security/oauth2/server/authorization/authentication/OAuth2DeviceAuthorizationRequestAuthenticationToken.java
@@ -96,7 +96,7 @@ public OAuth2DeviceAuthorizationRequestAuthenticationToken(Authentication client
 		this.deviceCode = deviceCode;
 		this.userCode = userCode;
 		this.authorizationUri = null;
-		this.additionalParameters = null;
+		this.additionalParameters = Collections.emptyMap();
 		setAuthenticated(true);
 	}
 
diff --git a/oauth2-authorization-server/src/main/java/org/springframework/security/oauth2/server/authorization/authentication/OAuth2DeviceVerificationAuthenticationToken.java b/oauth2-authorization-server/src/main/java/org/springframework/security/oauth2/server/authorization/authentication/OAuth2DeviceVerificationAuthenticationToken.java
index 114d11b39..0f0fc48c5 100644
--- a/oauth2-authorization-server/src/main/java/org/springframework/security/oauth2/server/authorization/authentication/OAuth2DeviceVerificationAuthenticationToken.java
+++ b/oauth2-authorization-server/src/main/java/org/springframework/security/oauth2/server/authorization/authentication/OAuth2DeviceVerificationAuthenticationToken.java
@@ -80,7 +80,7 @@ public OAuth2DeviceVerificationAuthenticationToken(Authentication principal, Str
 		this.principal = principal;
 		this.userCode = userCode;
 		this.clientId = clientId;
-		this.additionalParameters = null;
+		this.additionalParameters = Collections.emptyMap();
 		setAuthenticated(true);
 	}