This project is not covered by Drupal’s security advisory policy.

Enables "Shared Sign-Ons" between related Drupal sites on one server with a shared database. Can be used standalone, but is most tested in conjunction with the domain (aka Domain Access) module.

This project has been marked as insecure by Drupal Security Team. All of it's releases have been unpublished. Disable the module and remove it from your site.
If you still want to use Single Sign On on your sites, Single Sign On module has been created as a successor to Shared Sign On.

Project Information