Corrupted files are uploaded

[Dwells]

Hello, for many years, I have been facing this bug.
I connect to my servers (under Debian 9 and 10) using sftp protocol from a PC with Windows 10. And occasionally, when uploading a file to the server, it turns out to be broken.
In 90% of cases, it helps to re-upload it several times. But sometimes, I have to restart FileZilla.
The files I'm talking about have .tpl extension and contain html, smarty and php code inside.
Help me please...

[botg]

Unless you operate an isolated network in a tech history museum, you very much want to update your server operating systems.

Which version of FileZilla are you using?

Which SFTP server software are you using?

[Dwells]

Thanks for your answer!
FileZilla is always updated, the current version is 3.65.0

Code: Select all

 dpkg -l | grep -E 'openssh-server|proftpd-b asic|vsftpd'
ii  openssh-server 1:7.9p1-10+deb10u2 amd64        secure shell (SSH) server, for secure access from remote machines
ii  proftpd-basic 1.3.6-4+deb10u6 amd64        Versatile, virtual-hosting FTP daemon - binaries

Code: Select all

cat /etc/debian_version
10.13

I don't consider it very old software.

[iam_sysop]

Debian Stretch (v9) is no longer even on Debain's support matrix. That means no patches for OpenSSH have been applied to it for years.
Debian Buster(v10) has not patched the available versions of OpenSSHd (including yours) up to the current vulnerabilities:
Debian Buster (v10) has not patched vulnerabilities in the prodtpd release installed on your system.

https://security-tracker.debian.org/tra ... ge/openssh
https://security-tracker.debian.org/tra ... oftpd-dfsg

botg has the proper advice -- you cannot diagnose issues when you are operating software that is not at a minimum up to security standards. You're trying to run a new client with new updates and security defaults against an extremely old (and unpatched server). This will not be able to be diagnosed easily due to the multitude of possibilities of mismatched features between client and server at this point.

[botg]

What is the nature of the corruption? If you look at the corrupted file, how does it differ from the original?