diff --git a/monkey/infection_monkey/puppet/mock_puppet.py b/monkey/infection_monkey/puppet/mock_puppet.py
index 0652c109b..674908c14 100644
--- a/monkey/infection_monkey/puppet/mock_puppet.py
+++ b/monkey/infection_monkey/puppet/mock_puppet.py
@@ -154,7 +154,7 @@ class MockPuppet(IPuppet):
             return (False, None)
 
         if host == DOT_3:
-            return (True, "Linux")
+            return (True, "linux")
 
         if host == DOT_4:
             return (False, None)