It has been discovered that lftp up to and including version 4.8.3 does not properly sanitize remote file names, leading to a loss of integrity on the local system when reverse mirroring is used. A remote attacker may trick a user to use reverse mirroring on an attacker controlled FTP server, resulting in the removal of all files in the current working directory of the victim's system.
https://usn.ubuntu.com/3731-2/
https://github.com/lavv17/lftp/issues/452
https://github.com/lavv17/lftp/commit/a27e07d90a4608ceaf928b1babb27d4d803e1992
https://bugzilla.redhat.com/show_bug.cgi?id=CVE-2018-10916
http://lists.opensuse.org/opensuse-security-announce/2019-04/msg00010.html
http://lists.opensuse.org/opensuse-security-announce/2019-03/msg00036.html