diff --git a/src/Types/Auth.ts b/src/Types/Auth.ts
index 0838c3fa..f1e61625 100644
--- a/src/Types/Auth.ts
+++ b/src/Types/Auth.ts
@@ -68,6 +68,7 @@ export type AuthenticationCreds = SignalCreds & {
 	pairingCode: string | undefined
 	lastPropHash: string | undefined
 	routingInfo: Buffer | undefined
+	additionalData?: any | undefined
 }
 
 export type SignalDataTypeMap = {
diff --git a/src/Utils/auth-utils.ts b/src/Utils/auth-utils.ts
index e20144ca..9661d0c6 100644
--- a/src/Utils/auth-utils.ts
+++ b/src/Utils/auth-utils.ts
@@ -325,6 +325,7 @@ export const initAuthCreds = (): AuthenticationCreds => {
 		registered: false,
 		pairingCode: undefined,
 		lastPropHash: undefined,
-		routingInfo: undefined
+		routingInfo: undefined,
+		additionalData: undefined
 	}
 }