This release addresses a potential timing attack on pages or documents that have been protected with a shared password through Wagtail's "Privacy" controls. This password check is performed through a character-by-character string comparison, and so an attacker who is able to measure the time taken by this check to a high degree of accuracy could potentially use timing differences to gain knowledge of the password. (This is `understood to be feasible on a local network, but not on the public internet <https://groups.google.com/d/msg/django-developers/iAaq0pvHXuA/fpUuwjK3i2wJ>`_.)
Many thanks to Thibaud Colas for reporting this issue.