diff --git a/libcxx/utils/libcxx/test/executor.py b/libcxx/utils/libcxx/test/executor.py
--- a/libcxx/utils/libcxx/test/executor.py
+++ b/libcxx/utils/libcxx/test/executor.py
@@ -158,6 +158,17 @@
                 srcs.extend(file_deps)
                 dsts.extend(dev_paths)
             self.copy_in(srcs, dsts)
+
+            # When testing executables that were cross-compiled on Windows for
+            # Linux, we may need to explicitly set the execution permission to
+            # avoid the 'Permission denied' error:
+            chmod_cmd = ['chmod', '+x', target_exe_path]
+            chmod_cmd, out, err, rc = self._execute_command_remote(chmod_cmd,
+                                                                   target_cwd,
+                                                                   env)
+            if rc != 0:
+                return (chmod_cmd, out, err, rc)
+
             # TODO(jroelofs): capture the copy_in and delete_remote commands,
             # and conjugate them with '&&'s around the first tuple element
             # returned here: