Telnet Connection Failing

Hello, I installed Luci version 17.01.4 on my WRT 3200 ACM, and cannot currently access through telnet. I read that telnet connection was closed in the new version, and there I must manually enable it. Following this:

I tried using the patch command in step 2, but it seems that nothing is recognizable. Is there any other solution to enabling access through telnet? Thanks.

telnet is neither supplied nor supported in recent releases. ssh is "required" for shell access

Is there any way I can downgrade versions?

Not without opening security holes in addition to telnet. It's very hard to come up with a compelling reason to enable telnet in this day age. Perhaps you've got one and can describe why ssh or other more secure access methods can't meet your needs.

I'm testing a security application for a project on my personal router which requires telnet to be enabled. I attempted to downgrade Chaos Calmer from another link (As the official download link is taken down by OpenWRT for WRT 3200 ACM router), but I cannot access the router panel through its IP, nor telnet, even once downloading that image.

Telnet is not supported in stock OpenWRT. If you have a firmware that is purported to have telnet, you should contact the distributor of that file.

Also, it may be a config issue with downgrading, try resetting the router.

Any idea as to where I may be able to go to download a working version of chaos calmer for my router (Or any other previous version with telnet)? The one posted on the openwrt archived files for the Linksys WRT 3200 ACM router has been taken down, and I can't seem to find another that seems to work.

If you have a newer WRT3200ACM (manfuactured ~Nov 17 or later) CC images won’t work anyway.
You would need to patch/build them yourself.

At which point, it would be simpler to just include telnet in a custom build of 17.04

How would I do that?

I suggest building an image that will suit your needs. See:

@brandon95, be careful with unknown images! This issue with older devices may be why your device is unaccessible now (and why the images were taken down)!

I see, thank you for your help

Would this work? It says successfuly tested in LEDE 17.01. However, when I try the "patch" command it is not recognized. I then used apt-get to try and install it inside the OS of the router, but apt-get isn't recongized as well.

OpenWRT does not use uses opkg. What are you trying to install, exactly?

What do you mean by:

What is the patch command!?!? You do understand you have to compile a firmware, right???


The picture you posted says itself: "Copy the above content to a file into the build root..." so why are you typing the content as commands into the router???

I'll reiterate:

The developer's Wiki link above should be helpful to you.

Alright I see, so this is for enabling telnet in a custom build of OpenWRT. I'll take a look at it, appreciate the help.

I'd pick and choose from that patch, as it replaces ssh (dropbear) with telnet. If you compile telnetd in, you can manually start it, or use an appropriate procd script to start it.

Are you sure it requires telnet to be enabled, and not just that you can reach a shell? Is this project something like "show my college computer security class that certain protocols can be sniffed on the wire by implementing this sniffing myself using an example system" because short of a demonstration of how insecure something like telnet is there is no actual real-world reason to run a telnet server on your router

Literally everything that can be done by telnetting into a shell on a router can be done by ssh instead. Anything that requires you to connect to an arbitrary port on your router could be done by having a telnet client just installed on your PC without installing a telnet server on your router. I really can't see what a telnet daemon could possibly help you do. But I'm willing to imagine that I just haven't thought of the very unusual application you've got... still I think you should re-assess whether you really need to connect to a telnet daemon.

1 Like

I'll echo the question @jeff asked which was never addressed:

  • "Perhaps you’ve got one and can describe why ssh or other more secure access methods can’t meet your needs."

Telnet on a single user OS is flat out asking for a security breach to occur, as it allows unfettered, unauthenticated access as root.

  • OpenWrt removed telnet completely in early to mid 2015, and there shouldn't be any reason as to why SSH cannot be utilized... I personally would ask for clarification from whomever is managing your project, as enabling telnet on your personal WAN facing router substantially raises the risk of compromising your entire LAN.