diff --git a/ccmlib/node.py b/ccmlib/node.py
index c417ac7f..6fc6bdfd 100644
--- a/ccmlib/node.py
+++ b/ccmlib/node.py
@@ -2099,9 +2099,9 @@ def log_line_category(line):
 
 def handle_external_tool_process(process, cmd_args):
     out, err = process.communicate()
-    if out and isinstance(out, bytes):
+    if (out is not None) and isinstance(out, bytes):
         out = out.decode()
-    if err and isinstance(err, bytes):
+    if (err is not None) and isinstance(err, bytes):
         err = err.decode()
     rc = process.returncode