I've obtained a shell on an embeded device, a /bin/sh shell, but it is extremely limited; It just allows me to run a few commands with specific arguments, like ifconfig, or iptables, or cat (but not cat whateverIwant, only cat /proc/cpuusage for example), I've been able to bypass this shell, and execute any command, or kind of; basically I can try to run any command (lets say, ping for example) but sh would not have rights to do it.Errors:Trying to write to an existing file/bin/sh: cannot create /bin/ping: Text file busyTrying to run ping/bin/sh: Access Denied.So the scenario is that I can run only very specific useless commands, and also I've been able to write to files and to read filenames (not read files), note that, I can't write certain files, i.e. to binaries being used, but I can write new files. The only idea I have that would help me running code is using some kind of dll hijacking method like it is done in windows, but I don't know if this is even doable.EDIT: Additional Info -> The device has 2 usb ports, and has a ftp service. I connect using telnet.
Running code when /bin/sh has no rights
account restrictions;restricted shell