It seems the password is not being accepted by the remote server.

The debugging output shows that the script hangs because the remote server accepts both password and keyboard-interactive authentication, a case where Net::SFTP::Foreign can't handle correctly failed password authentication.

A possible workaround is to force the authentication method to be either password or keyboard-interactive, for instance:

my $sftp = Net::SFTP::Foreign->new(...,
                                   more => [-o => 'PreferredAuthentica
+tions=keyboard-interactive']);
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Another possibility is to connect to the remote host via Net::OpenSSH which has a more sophisticated login algorithm, able to detect errors that Net::SFTP::Foreign doesn't:

my $ssh = Net::OpenSSH->new(...);
my $sftp = $ssh->sftp;
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