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The Day the Telnet Died

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Re: The Day the Telnet Died

#121

Post by tokyobreakfast »

paulddraper wrote: post #118
tokyobreakfast wrote: post #109

An RCE in GNU's telnetd has no relationship to the sunsetting of telnet. Something could equally likely happen with SSH (but not really because the OpenBSD folks are paranoid by nature). Apple removing the telnet client from OS X was a stupid move. How can you call yourself UNIX and not have a telnet client? It's like removing grep or ed.

There's no UNIX requirement for telnet. Ubuntu does not include it by default (starting 16.04?). Most most distros don't.

Two wrongs don't make a right.

Apple still includes uucp for some unknown reason.

The saving disk space argument makes no sense because telnet was one of the smaller binaries in /usr/bin.

Telnet continues to be widely used for select use cases and being told we're naughty by not including it feels punitive and just adds extra steps. What are you supposed to do, trash a $1m piece of industrial equipment because Apple wants to remind you Telnet is insecure?

New devices are still being released with Telnet where SSH is impractical or unnecessary.

Re: The Day the Telnet Died

#122

Post by badc0ffee »

tokyobreakfast wrote: post #109

An RCE in GNU's telnetd has no relationship to the sunsetting of telnet. Something could equally likely happen with SSH (but not really because the OpenBSD folks are paranoid by nature). Apple removing the telnet client from OS X was a stupid move. How can you call yourself UNIX and not have a telnet client? It's like removing grep or ed.

There's always nc hostname 23 unless you need authentication

Re: The Day the Telnet Died

#123

Post by [deleted] »

tokyobreakfast wrote: post #121
paulddraper wrote: post #118

Earlier quoted context omitted.

There's no UNIX requirement for telnet. Ubuntu does not include it by default (starting 16.04?). Most most distros don't.

Two wrongs don't make a right. Apple still includes uucp for some unknown reason. The saving disk space argument makes no sense because telnet was one of the smaller binaries in /usr/bin. Telnet continues to be widely used for select use cases and being told we're naughty by not including it feels punitive and just adds extra steps. What are you supposed to do, trash a $1m piece of industrial equipment because Apple…

[deleted]

Re: The Day the Telnet Died

#124

Post by taftster »

roywiggins wrote: post #120
taftster wrote: post #105

Earlier quoted context omitted.

Well, I mean, the first part is a song by Don McLean called American Pie. You might know that, unsure that everyone will pick it out though. One of the most famous play choices at karaoke bars these days too. I think because the song is a long story, of sorts? But it's a terribly long song and I will leave to take a smoke break anytime it gets chosen. You're going to be there for a good 10 minutes before it concludes…

The rest of it seems to be substantially edited by an LLM too, or at least it's composed much like LLM outputs often are these days: “not a gradual decline, not scanner attrition, not a data pipeline problem, but a step function.” "Not X, not Y, not Z" is a common LLM tic, and there's a few more like it in there.

I mean, that's fair. I guess I just wanted to put my old man hat on. The song is a tribute to an era of lost innocence. Which I think is quite apropos to the current situation surrounding telnet. Vestiges of the days of the early internet continue to disappear, almost like an endangered species. Old/obsolete protocols, like telnet, are pined for by old guys like me.

Re: The Day the Telnet Died

#125

Post by mmh0000 »

tokyobreakfast wrote: post #121
paulddraper wrote: post #118

Earlier quoted context omitted.

There's no UNIX requirement for telnet. Ubuntu does not include it by default (starting 16.04?). Most most distros don't.

Two wrongs don't make a right. Apple still includes uucp for some unknown reason. The saving disk space argument makes no sense because telnet was one of the smaller binaries in /usr/bin. Telnet continues to be widely used for select use cases and being told we're naughty by not including it feels punitive and just adds extra steps. What are you supposed to do, trash a $1m piece of industrial equipment because Apple…

There are many things I want to say in reply to this. So I’ll bullet point them:

* yes, do not buy equipment that has acquired so much tech debt that it still requires telnet.

* there are a million telnet clients out in the world. And ones far better than the default OS one. Apple not shipping one standard is not the end of the world or really anything more than a mild inconvenience for the small handful of people who need actual “Telnet” as opposed to Netcat or socat, both of which are far better than base Telnet.

Re: The Day the Telnet Died

#126

Post by otterley »

Sparkyte wrote: post #112

Between you and me telnet is not dead. Sometimes I use it to probe a port to verify it is working.

That's not really telnet. Yeah, it's using the same client, but the server and underlying protocol are what's relevant here.

The modern replacement for telnet used in the "probe a port" fashion is nc/netcat.

Re: The Day the Telnet Died

#127

Post by Fnoord »

Sparkyte wrote: post #112

Between you and me telnet is not dead. Sometimes I use it to probe a port to verify it is working.

You might wanna use netcat for that instead [1]. Or, for example, socat [2]. Netcat has been around for a long, long time now.

[1] nc (1) - arbitrary TCP and UDP connections and listens

[2] socat (1) - Multipurpose relay (SOcket CAT)

Re: The Day the Telnet Died

#128

Post by AnonHP »

So Telnet as a client is not dead though, right? A long time ago, I used to use the Telnet client to talk to SMTP servers (on port 25) and send spoofed emails to friends for fun.

With port blocking widening in scope, I’ve long believed that we would one day have every service and protocol listening on port 443. Since all other ports are being knocked off in the name of security, we’ll end up having one port that makes port based filtering useless.

Re: The Day the Telnet Died

#129

Post by otterley »

RupertSalt wrote: post #101
jopython wrote: post #45

This is about Telnetd. Not telnet itself.

1. TELNET is an IETF-standard protocol defined by RFCs. 2. Telnet is a well-known port assigned by the IANA (tcp/23). 3. telnet is a client program, originated on Unix, available on many systems, and likely from a quite homogeneous codebase. 4. telnetd is a server program, also originated on Unix for the purpose of implementing Telnet protocol as a login server. Also a homogeneous codebase or two. TFA is about items…

I'm not sure I understand how this argument refutes the claim that this isn't about telnetd. There'd be no reason to respond to the vulnerability in the way they did if the vulnerability in telnetd hadn't existed and been exploited -- and the proof is that nobody ever did until now.

Re: The Day the Telnet Died

#130

Post by mmh0000 »

bentcorner wrote: post #93
catskull wrote: post #28

When I was an intern for some reason they issued me a voip phone for my desk. One day I got bored and figured out I could telnet into it. Nothing interesting but it was still a fun moment for me!

A very very long time ago as an intern I was working on a perl cgi script and I would often test it with telnet. I was used to messing around with hayes commands so manually typing in HTTP commands seemed like a natural extension of that.

If you miss that and long for the olden days, you can still do it today with OpenSSL’s sclient:

  openssl s_client -connect www.yahoo.com:443
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