diff --git a/modules/viBidAdapter.js b/modules/viBidAdapter.js
index 8d8cb06e47e4..3e06e9617fef 100644
--- a/modules/viBidAdapter.js
+++ b/modules/viBidAdapter.js
@@ -303,6 +303,7 @@ export function mergeArrays(hashFn, ...args) {
 }
 
 export function documentFocus(doc) {
+  if (!doc) return undefined;
   return typeof doc.hasFocus === 'function' ? +doc.hasFocus() : undefined;
 }
 
diff --git a/test/spec/modules/viBidAdapter_spec.js b/test/spec/modules/viBidAdapter_spec.js
index 8f1c07047ec9..78b891201373 100644
--- a/test/spec/modules/viBidAdapter_spec.js
+++ b/test/spec/modules/viBidAdapter_spec.js
@@ -906,6 +906,7 @@ describe('documentFocus', () => {
         hasFocus: () => false
       })
     ).to.equal(0);
+    expect(documentFocus()).to.be.undefined;
     expect(documentFocus({})).to.be.undefined;
   });
 });