diff --git a/src/auth/passdb-ldap.c b/src/auth/passdb-ldap.c
index 6c432af..69624a1 100644
--- a/src/auth/passdb-ldap.c
+++ b/src/auth/passdb-ldap.c
@@ -519,7 +519,8 @@ passdb_ldap_preinit(struct auth_passdb *auth_passdb, const char *args)
 			  conn->set.auth_bind ? "password" : NULL);
 	module->module.cache_key =
 		auth_cache_parse_key(auth_passdb->auth->pool,
-				     conn->set.pass_filter);
+				     t_strconcat(conn->set.base,
+						 conn->set.pass_filter, NULL));
 	module->module.default_pass_scheme = conn->set.default_pass_scheme;
 	return &module->module;
 }
diff --git a/src/auth/userdb-ldap.c b/src/auth/userdb-ldap.c
index 05f6eb7..9150654 100644
--- a/src/auth/userdb-ldap.c
+++ b/src/auth/userdb-ldap.c
@@ -231,7 +231,8 @@ userdb_ldap_preinit(struct auth_userdb *auth_userdb, const char *args)
 			  conn->user_attr_map, default_attr_map, NULL);
 	module->module.cache_key =
 		auth_cache_parse_key(auth_userdb->auth->pool,
-				     conn->set.user_filter);
+				     t_strconcat(conn->set.base,
+						 conn->set.user_filter, NULL));
 	return &module->module;
 }