diff --git a/lib-ee/emqx_ee_connector/src/emqx_ee_connector_influxdb.erl b/lib-ee/emqx_ee_connector/src/emqx_ee_connector_influxdb.erl
index 1370ed2c2..402202b11 100644
--- a/lib-ee/emqx_ee_connector/src/emqx_ee_connector_influxdb.erl
+++ b/lib-ee/emqx_ee_connector/src/emqx_ee_connector_influxdb.erl
@@ -341,9 +341,10 @@ password(_) ->
 redact_auth(Term) ->
     emqx_misc:redact(Term, fun is_auth_key/1).
 
-is_auth_key(<<"Authorization">>) -> true;
-is_auth_key(<<"authorization">>) -> true;
-is_auth_key(_) -> false.
+is_auth_key(Key) when is_binary(Key) ->
+    string:equal("authorization", Key, true);
+is_auth_key(_) ->
+    false.
 
 %% -------------------------------------------------------------------------------------------------
 %% Query
@@ -628,6 +629,13 @@ is_unrecoverable_error(_) ->
 -ifdef(TEST).
 -include_lib("eunit/include/eunit.hrl").
 
+is_auth_key_test_() ->
+    [
+        ?_assert(is_auth_key(<<"Authorization">>)),
+        ?_assertNot(is_auth_key(<<"Something">>)),
+        ?_assertNot(is_auth_key(89))
+    ].
+
 %% for coverage
 desc_test_() ->
     [