You can limit the attachments size and number by going to the manage add ons section as shown on the right.
Search for JAM at the buttom left and click on "Attachment configuration"
Or press "g+g" and type attachments configuration" the below screen will show
From this page you can select the project that you wish to imply the restriction on and set the Max number of attachments and Max number of attachment size per Mb
You can disable the attachment configuration by selecting the option off in the top of the page |