Attachments added via copy & paste state that they've been by admin instead of the user editing the page

When uploading an attachment/image via copy & paste from clipboard inside the ckeditor the resulting attachment states that it was uploaded by admin instead of the user doing the edits.

1. Edit a page
2. Do a screenshot via e.g. Greenshot on Windows or Spectacle on Linux and copy it to clipboard
3. paste it into the ckeditor

5. save and see admin instead of the editing user in the attachment infos who uploaded the attachment

When uploading an attachment via the upload button instead everything is working as you'd expect and the attachment correctly states it was uploaded by the editing user.