diff --git a/src/authenticators/ldap_ynhuser.py b/src/authenticators/ldap_ynhuser.py
index 31378526d..8a5fef9d4 100644
--- a/src/authenticators/ldap_ynhuser.py
+++ b/src/authenticators/ldap_ynhuser.py
@@ -199,6 +199,7 @@ class Authenticator(BaseAuthenticator):
             path="/",
             # Doesn't this cause issues ? May cause issue if the portal is on different subdomain than the portal API ? Will surely cause issue for development similar to CORS ?
             samesite="strict" if not is_dev else None,
+            domain=f".{request.get_header('host')}",
         )
 
         # Create the session file (expiration mechanism)