diff --git a/lib/fpm/util.rb b/lib/fpm/util.rb
index 3beece1d5e..0fd01e6fac 100644
--- a/lib/fpm/util.rb
+++ b/lib/fpm/util.rb
@@ -24,6 +24,8 @@ class ProcessFailed < StandardError; end
 
   # Is the given program in the system's PATH?
   def program_in_path?(program)
+    # return false if path is not set
+    return false unless ENV['PATH']
     # Scan path to find the executable
     # Do this to help the user get a better error message.
     envpath = ENV["PATH"].split(":")