Hi Carlos,
I would not normally expect system files to have non-default permissions.
As these routers are new to you, the first thing I would recommend you do is re-flash them using flash writer to install the firmware version that you require.
This will bypass any file permissions and also factory reset the router so you can be sure you have a known good file system and config.
Flashwriter can be downloaded from this page: http://www.digi.com/support/productdetail?pid=4112&type=firmware
Usage instructions are here: http://ftp1.digi.com/support/firmware/TPS_FlashWriter.htm
Firmware is available from here: http://www.sarians.co.uk/firmware/flashwriter/
Make sure you load on the correct firmware for either the Novatel or Option WAN module. If unsure what firmware to install, I'll need to see the output from the CLI command 'ati5'.