Model :

Hardware Version : Not Clear

Firmware Version :

ISP :

Hello,

I've been looking into automating the firmware upgrade process of our routers, and have found that while telnet is closed it does seem to have a SSH port open. As evidenced by this nmap scan:
[code]Starting Nmap 6.40 ( http://nmap.org ) at 2015-10-08 08:21 CEST
Nmap scan report for 192.168.0.1
Host is up (0.00063s latency).
Not shown: 996 closed ports
PORT STATE SERVICE
22/tcp open ssh
80/tcp open http
1900/tcp open upnp
49152/tcp open unknown
MAC Address: 30:B5:C2:D9:D1:0E (Unknown)
Device type: general purpose
Running: Linux 2.6.X
OS CPE: cpe:/o:linux:linux_kernel:2.6
OS details: Linux 2.6.23 - 2.6.38
Network Distance: 1 hop[/code]

However, when I try to log into the service, this happens:
[code]$ ssh admin@192.168.0.1
admin@192.168.0.1's password:
PTY allocation request failed on channel 0
shell request failed on channel 0
[/code]

After some searching I've come to find that this is a problem that's either solved by mounting /dev/pts in fstab, which I can't do without SSH access, or by running an interactive session of bash manually. Trying the latter, this happens:
[code]$ ssh admin@192.168.0.1 "/bin/bash -i"
admin@192.168.0.1's password:
exec request failed on channel 0[/code]
Even tried with plain old sh, with the same result.

The question then is: Is it possible to upgrade the firmware via SSH, and if so could someone please be so kind as to tell me how?

Thanks. :)