Add Bulk Labels to Space Attachments

Select Label Manager from Space Tools menu
Click Add Bulk Labels tab from Attachment Labels Operation menu and enter the name of the label(s) to be added.
Select attachments to add labels to attachments.
For Large Spaces

If a page contains too many child pages, please select "All attachments in this space will be affected" option.
A confirmation screen will be displayed on the following step. Click next to continue.
After content selection and process completed a success message will be displayed

Label Manager for Confluence