Question Anyway to enable telnet on C6900?

nasch007

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May 30, 2016
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Greetings,

I'm trying to enable telnet on Netgear C6900 (costco)

I'd like to update firmware to DD-WRT.

From an Admin command prompt...

tried telnetenable2.exe and got the following output:
starting...
creating pkt...
sending pkt...
done.

tried telnet 192.168.0.1 and could not open connection to the host, on port 23: Connect failed

tried nte 0.5 nte.exe -debug produces the following:
debug: 0xffffffff .
MAC0: >a0:40:a0:3a:a0:a2<.
MAC1: >A040A03AA0A2<.
user: >admin<.
pass: >pass<.
getaddrinfo():
ai_family = 2, ai_socktype = 0, ai_protocol = 17
ai_addrlen = 16, ai_addr->sa_family = 2.
ai_flags = 0x00000004.
ai_addr->sa_data[ 2: 5] = 192.168.0.1
dns_resolve() sts = 0.
sock = 224, FD_SETSIZE = 64,
FD_ISSET( sock, &fds_rec) = 1.
pre-select(1). sock = 224.
pre-recvfrom(). sock = 224.
nte: recvfrom() failed.
nte: errno = 0, WSAGLA() = 10054.
nte: No error

C:\Users\Nate\Downloads\nte-05_win\nte-05\win32\Release>telnet 192.168.0.1
Connecting To 192.168.0.1...Could not open connection to the host, on port 23: Connect failed

C:\Users\Nate\Downloads\nte-05_win\nte-05\win32\Release>nte m=a0:40:a0:3a:a0:a2 n=192.168.0.1 u=admin p=pass
nte: recvfrom() failed.
nte: errno = 0, WSAGLA() = 10054.
nte: No error

I've factory reset the router and changed the admin password. I'm connected directly from my desktop to the modem/router and using the mac addy under LAN Port.

The firmware version currently on this hunk a junk is V1.01.27.

I've disabled Windows Firewall while doing this experiment.

I'm at my wit's end right now. Cannot seem to get the python script to run on Windows, after fixing various print issues, finally got an import error: no module named Crypto. Changed it to crypt using IDLE, but get an error: crypt not supported on Windows.

Tried on my macbook pro brew install python easy_install python-dev then running the script....
I finally got it to run and I do get "payload sent to 192.168.0.1:23", but telnet still says connection refused... argh.

I'm wondering if at this point I've just got crappy firmware that can't be updated.

Is there any other way to do this?

Any help would be appreciated.
 
In most cases telnet is not enabled by default it is not secure. Some routers support SSH instead.

You best test is going to be to run wireshark or something to capture the data. Then telnet to the router IP. You will likely see a SYN packet going to port 24 and the router either send a RST or ignore the packet. This means telnet is not running on the router. If the router even has telenet support you would need to enable it in that case.

Still unless you are much more ambitious than most you will never get dd-wrt or any other third party firmware to run on that device. Any device that contains a modem needs the drivers and firmware images for the modem chipsets. These generally have copyright licensees that prevent them from being combined and distributed in other firmware. So the people building the dd-wrt images are not allowed to put the drivers into the image.

Now if you can actually get the driver for the modem you can build and link them in to the dd-wrt image yourself. For DSL modems you will find instructions if you look hard enough. For cable modems these drivers are not so easy to get. In many cases the firmware is locked by the ISP. The ISP will force updates so their network has a consistent modem firmware level to make their support easier. It also prevents hackers from designing devices that bypass their security and allow people to steal internet service.
 

nasch007

Distinguished
May 30, 2016
44
0
18,530
In most cases telnet is not enabled by default it is not secure. Some routers support SSH instead.

You best test is going to be to run wireshark or something to capture the data. Then telnet to the router IP. You will likely see a SYN packet going to port 24 and the router either send a RST or ignore the packet. This means telnet is not running on the router. If the router even has telenet support you would need to enable it in that case.

Still unless you are much more ambitious than most you will never get dd-wrt or any other third party firmware to run on that device. Any device that contains a modem needs the drivers and firmware images for the modem chipsets. These generally have copyright licensees that prevent them from being combined and distributed in other firmware. So the people building the dd-wrt images are not allowed to put the drivers into the image.

Now if you can actually get the driver for the modem you can build and link them in to the dd-wrt image yourself. For DSL modems you will find instructions if you look hard enough. For cable modems these drivers are not so easy to get. In many cases the firmware is locked by the ISP. The ISP will force updates so their network has a consistent modem firmware level to make their support easier. It also prevents hackers from designing devices that bypass their security and allow people to steal internet service.
Thank you for your reply. The router's web management interface has no options to enable Telnet, nor update stock firmware. Which really sucks... Netgear's knowledgebase articles confirm updates much be pushed by the ISP, however my ISP (Cox) refuses to do it. Despite the modem being on their support website, and despite Netgear stating a different approved firmware revision for cox. I provided images of both of these to tech support, and was brushed off. Sigh.

I can get wireshark and intercept the traffic and see, but darn the point about the modem drivers... I'm pretty much boned, then?

I did find this article, that seems to indicate the C7000 R7000 firmware worked well, but this was an older model possibly, or a different hardware revision, or different initial firmware. https://forum.dd-wrt.com/phpBB2/viewtopic.php?t=301328&sid=ccf1fc8b96fb0d0e09a753319fad8420

I guess if I'm stuck, I'm stuck. But this all comes from periodic intermittent internet loss and related DOS, Syn flood, and Teardrop attacks. See image: http://s000.tinyupload.com/index.php?file_id=00750087797732432830

Is this normal?


EDIT: I'm an idiot... it is the R6900 in the article, not the C6900... not the gateway but just a router. Shucks.

EDIT: I did find Netgear offers their open source firmware under GPL license.. the closest I could find was C7000... apparently the only difference in specs is that the c7 has a usb port, and is sold everywhere but Costco... but the C6900 has no usb port and is sold exclusively at Costco. https://kb.netgear.com/2649/NETGEAR-Open-Source-Code-for-Programmers-GPL now I would have to get someone to build if I had a way to flash it.

Thanks for your response, anyways.
 
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