Exploiting Embedded Systems – Part 4 – /dev/ttyS0

So far in this series we’ve found that we can log in to our target TEW-654TR router by either retrieving the plain text administrator credentials via TFTP, or through SQL injection in the login page. But the administrative web interface is just too limited – we want a root shell!… Continue reading

Exploiting Embedded Systems – Part 3 – /dev/ttyS0

In part 2 of this series we found a SQL injection vulnerability using static analysis. However, it is often advantageous to debug a target application, a capability that we’ll need when working with more complex exploits later on. In this segment we won’t be discovering any new vulnerabilities, but instead… Continue reading

Exploiting Embedded Systems – Part 2 – /dev/ttyS0

In part 1 we used the TEW-654TR’s TFTP service to retrieve the administrative credentials to our target system. But what if we didn’t have access to the TFTP service? Many embedded devices don’t have a TFTP service, or there may be a firewall between us and the target that blocks… Continue reading

Modifying The DD-WRT GUI – /dev/ttyS0

Although released under the GPL, DD-WRT is notoriously difficult to build from source. If you want to customize your DD-WRT installation, it is usually easier to extract files from the firmware image, change what you need, and then re-construct the image. One exception here is the Web GUI. The DD-WRT… Continue reading

Reverse Engineering VxWorks Firmware: WRT54Gv8 – /dev/ttyS0

The ability to analyze a firmware image and extract data from it is extremely useful. It can allow you to analyze an embedded device for bugs, vulnerabilities, or GPL violations without ever having access to the device. In this tutorial, we’ll be examining the firmware update file for the Linksys… Continue reading

Mystery File System – /dev/ttyS0

Last week Jim posted a comment asking about reverse engineering the firmware for some Chinese routers with the intention of extracting the Web files and translating them to English. Although I usually work with Linux based firmware, this sounded interesting so I thought I’d investigate. Although I wasn’t able to… Continue reading