Ftp errors caused by outdated proftpd module?

When transferring files through FTP, I am getting alot of ‘connection refused’ errors, so I decided to test my FTP connection on ftptest.net, with the following result:
I used explicit FTP over TLS, am running latest version of virtualmin/webmin on Ubuntu 16.04.

Status: Data connection established, performing TLS handshake…

Reply: 150 Opening BINARY mode data connection for MLSD

Status: TLS handshake successful, verifying certificate…

Status: Received 2 certificates from server.

Status: cert[0]: subject=‘CN=mydomain.com’ issuer=‘C=US,O=Let\27s Encrypt,CN=Let\27s Encrypt Authority X3’

Status: cert[1]: subject=‘C=US,O=Let\27s Encrypt,CN=Let\27s Encrypt Authority X3’ issuer=‘O=Digital Signature Trust Co.,CN=DST Root CA X3’

Status: TLS session of transfer connection has been resumed.

Error: Malformed directory listing

Error: Line feed received without preceding carriage return

Virtualmin/ubuntu comes with proftpd 1.3.5a pre-installed (proftpd -v) and after searching online it seems this is a known issue with this version:

Is it possible to update proftpd?

We don’t provide the proftpd package, your OS does. Has anyone filed a bug with the Ubuntu folks about the issue?

Ah, I see! Thanks for the information Joe, didn’t know that.
I’m actually not sure where to look for that, could you point me in the right direction perhaps? Only checked the proftpd forums where it was a known issue for version 1.3.5a. Any experience in updating proftpd?

Bug tracking for all Ubuntu packages is on Launchpad. The ProFTPd package is here: https://bugs.launchpad.net/ubuntu/+source/proftpd-dfsg

I’m browsing, but don’t see this issue immediately, but I need to figure out how to limit it to a specific version or Ubuntu release. You may be able to enable a newer repository for this one specific package (you’d need to make sure you only use it for this package, though, as a full dist-upgrade would break some things, including Virtualmin, as we don’t support non-LTS releases of Ubuntu due to the short lifecycle).

Edit: Here it is: https://bugs.launchpad.net/ubuntu/+source/proftpd-dfsg/+bug/1613737