Debian Linux Security Advisory 4922-1 - Amir Sarabadani and Kunal Mehta discovered that the import functionality of Hyperkitty, the web user interface to access Mailman 3 archives, did not restrict the visibility of private archives during the import, i.e. that during the import of a private Mailman 2 archive the archive was publicly accessible until the import completed.
285e96294fff62bc4ef42f9493107e61acf632573049b66584b40c1760babad2