Updated radicale package fixes security vulnerabilities:
If an attacker is able to authenticate with a user name like .*', he can
bypass read/write limitations imposed by regex-based rules, including the
built-in rules
ownerwrite' (read for everybody, write for the calendar
owner) and `owneronly' (read and write for the the calendar owner)
(CVE-2015-8748).
The radicale package has been updated to version 1.1.1, fixing this issue and several other security issues.