Software engineer Chris Wellons writes about tar-pitting nefarious SSH probes. Anyone with a publicly-facing SSH server knows that it is probed from the moment it is turned on. Usually, the overwhelming majority of incoming connection attempts are malevolent in nature. There are several ways to deal with these attempts, one method is to drag out the response for as long as possible.
This program opens a socket and pretends to be an SSH server. However, it actually just ties up SSH clients with false promises indefinitely — or at least until the client eventually gives up. After cloning the repository, here’s how you can try it out for yourself (default port 2222):
[...] Your SSH client will hang there and wait for at least several days before finally giving up. Like a mammoth in the La Brea Tar Pits, it got itself stuck and can’t get itself out. As I write, my Internet-facing SSH tarpit currently has 27 clients trapped in it. A few of these have been connected for weeks. In one particular spike it had 1,378 clients trapped at once, lasting about 20 hours.
(Score: 3, Interesting) by DannyB on Monday March 25 2019, @03:13PM
I also am aware that it is possible to have both SSH and SSL on the same port.
SSLH – Share A Same Port For HTTPS, SSH, And OpenVPN
https://www.ostechnix.com/sslh-share-port-https-ssh/ [ostechnix.com]
Applicative Protocol Multiplexer (e.g. share SSH and HTTPS on the same port)
https://github.com/yrutschle/sslh [github.com]
sslh – A ssl/ssh multiplexer
http://www.rutschle.net/tech/sslh/README.html [rutschle.net]
SSLH: A SSL/SSH Multiplexer for Linux
https://www.unixmen.com/sslh-a-sslssh-multiplexer-for-linux/ [unixmen.com]
(See also: Proxytunnel)
To transfer files: right-click on file, pick Copy. Unplug mouse, plug mouse into other computer. Right-click, paste.