diff --git a/lib/node.js b/lib/node.js
index c32843c59eb..83ad05c94f2 100644
--- a/lib/node.js
+++ b/lib/node.js
@@ -672,24 +672,24 @@ declare module "crypto" {
     size: number,
     callback: (err: ?Error, buffer: Buffer) => void
   ): void;
-  declare function randomFillSync(buffer: Buffer): void
-  declare function randomFillSync(buffer: Buffer, offset: number): void
+  declare function randomFillSync(buffer: Buffer | $TypedArray | DataView): void
+  declare function randomFillSync(buffer: Buffer | $TypedArray | DataView, offset: number): void
   declare function randomFillSync(
-    buffer: Buffer,
+    buffer: Buffer | $TypedArray | DataView,
     offset: number,
     size: number
   ): void
   declare function randomFill(
-    buffer: Buffer,
+    buffer: Buffer | $TypedArray | DataView,
     callback: (err: ?Error, buffer: Buffer) => void
   ): void
   declare function randomFill(
-    buffer: Buffer,
+    buffer: Buffer | $TypedArray | DataView,
     offset: number,
     callback: (err: ?Error, buffer: Buffer) => void
   ): void
   declare function randomFill(
-    buffer: Buffer,
+    buffer: Buffer | $TypedArray | DataView,
     offset: number,
     size: number,
     callback: (err: ?Error, buffer: Buffer) => void