diff --git a/index.js b/index.js
index 7da95e4..0bdca71 100644
--- a/index.js
+++ b/index.js
@@ -11,7 +11,7 @@ try {
   var parsed = toml.parse(str);
   var value = parsed;
   fields.forEach(function (f) {
-    value = value[f];
+    value = value?.[f];
   });
   core.setOutput("value", value);
 } catch (error) {