diff --git a/Lib/shutil.py b/Lib/shutil.py
index a4ce2c0..223e9a8 100644
--- a/Lib/shutil.py
+++ b/Lib/shutil.py
@@ -53,6 +53,9 @@
 _USE_CP_SENDFILE = hasattr(os, "sendfile") and sys.platform.startswith("linux")
 _HAS_FCOPYFILE = posix and hasattr(posix, "_fcopyfile")  # macOS
 
+# CMD defaults in Windows 10
+_WIN_DEFAULT_PATHEXT = ".COM;.EXE;.BAT;.CMD;.VBS;.JS;.WS;.MSC"
+
 __all__ = ["copyfileobj", "copyfile", "copymode", "copystat", "copy", "copy2",
            "copytree", "move", "rmtree", "Error", "SpecialFileError",
            "ExecError", "make_archive", "get_archive_formats",
@@ -1415,7 +1418,9 @@
             path.insert(0, curdir)
 
         # PATHEXT is necessary to check on Windows.
-        pathext = os.environ.get("PATHEXT", "").split(os.pathsep)
+        pathext_source = os.getenv("PATHEXT") or _WIN_DEFAULT_PATHEXT
+        pathext = [ext for ext in pathext_source.split(os.pathsep) if ext]
+
         if use_bytes:
             pathext = [os.fsencode(ext) for ext in pathext]
         # See if the given file matches any of the expected path extensions.