diff --git a/lib/module.js b/lib/module.js
index 29a23776d79..f633d62c490 100644
--- a/lib/module.js
+++ b/lib/module.js
@@ -170,6 +170,8 @@ Module._findPath = function(request, paths) {
     }
 
     if (!filename) {
+      if (exts === undefined)
+        exts = Object.keys(Module._extensions);
       filename = tryPackage(basePath, exts);
     }
 
diff --git a/test/fixtures/module-require/not-found/node_modules/module1/package.json b/test/fixtures/module-require/not-found/node_modules/module1/package.json
new file mode 100644
index 00000000000..b5018d73b21
--- /dev/null
+++ b/test/fixtures/module-require/not-found/node_modules/module1/package.json
@@ -0,0 +1,3 @@
+{
+  "main": "doesnotexist"
+}
diff --git a/test/fixtures/module-require/not-found/trailingSlash.js b/test/fixtures/module-require/not-found/trailingSlash.js
new file mode 100644
index 00000000000..4ac6cba9ca8
--- /dev/null
+++ b/test/fixtures/module-require/not-found/trailingSlash.js
@@ -0,0 +1 @@
+require('module1/');
diff --git a/test/parallel/test-require-exceptions.js b/test/parallel/test-require-exceptions.js
index e7a191b47ad..0e61ad2f3fd 100644
--- a/test/parallel/test-require-exceptions.js
+++ b/test/parallel/test-require-exceptions.js
@@ -14,9 +14,21 @@ assert.throws(function() {
 
 // Requiring a module that does not exist should throw an
 // error with its `code` set to MODULE_NOT_FOUND
-assert.throws(function() {
-  require(common.fixturesDir + '/DOES_NOT_EXIST');
-}, function(e) {
-  assert.equal('MODULE_NOT_FOUND', e.code);
-  return true;
-});
+assertModuleNotFound('/DOES_NOT_EXIST');
+
+assertExists('/module-require/not-found/trailingSlash.js');
+assertExists('/module-require/not-found/node_modules/module1/package.json');
+assertModuleNotFound('/module-require/not-found/trailingSlash');
+
+function assertModuleNotFound(path) {
+  assert.throws(function() {
+    require(common.fixturesDir + path);
+  }, function(e) {
+    assert.strictEqual(e.code, 'MODULE_NOT_FOUND');
+    return true;
+  });
+}
+
+function assertExists(fixture) {
+  assert(common.fileExists(common.fixturesDir + fixture));
+}