Skip to main content

Testing strategy for Controllers

Controllers are an essential part of ICS (Industrial Control Systems) network. Generally they are interface to many field devices such as sensors and placed within closed network. Exposing them outside world may be disastrous and they can be configured/ mis- configured to carry put attacks which can have dangerous impact on human being's life and safety.

So, it's necessary to do a security assessment of ICS networks to uncover potential vulnerabilties.
In brief, to test a controller we need to:
  • Understand the entire architecture- the platform, technologies, protocol it understands. Do a quick threat modeling here.
  • Review Network architecture, see how the controller is placed, ideally it should not be reachable from internet.
  • Firmware testing: Most of the controllers have embedded systems on them. Do a firmware testing here-
  • De compiling, modifying, patching, looking for hard coded sensitive credentials. How the firmware is uploaded/ downloaded- how secure is the mechanism.
  • Do host level review- Check if the controller is running any unnecessary/ insecure services, open ports, older software versions etc.
  • If web interface is enabled, do a testing from web app level security assessment.
  • If controller is using any proprietary or open source protocol, read the manual and try to understand the stack, what all security issues were discovered historically, what all tools are available in market to test them.
  • Get in touch with developers who work day in out with the technology.


Comments

Popular posts from this blog

SQL Injection in search field

Earlier I had written about performing SQL injection in search field and how to do a DoS attack and privilege escalation using 'Like' operators. Now another SQLi exploitation I came across recently. That too in the search field. This becomes important as lots of people don't pay much attention on the search forms/ fields in the application. My aim is to show that a search form can also be exploited with SQL Injection. The following queries are based on a real world exploitation. The steps and data are for just illustration purpose only. Suppose, the search form provides the details of users who have accessed the application some time and their login time details etc, we just need to provide their name in the search box provided. All the data were being going as Post request. So, to just fingerprint the database, I provide, 'nil'+'esh' in the search field and it successfully gives me the results. That means the database behind the application is concatenat…

File Upload through Null Byte Injection

Sometimes, during file upload we come across situation wherein there would be check on the file extension at the client side as well as server side too. If the application does allow only .jpeg extension to be uploaded, the client side java script checks for the extension of the file before passing the request. We all know that how easily this can be defeated.
Some applications, checks for the extension at the server side also. That's not easy to bypass. However there are some ways with which it still can be bypassed. Most of server side scripts are written in high level languages such as Php, Java etc who still use some C/C++ libraries to read the file name and contents. That leads to the problem. In C/C++ a line ends with /00 or which is called Null Byte. So whenever the interpreter sees a null byte at the end of the a string, it stops reading thinking it has reached at the end of the string.
This can be used for the bypass. It works for many servers, specially php servers. Th…

Insecure protocols

Some basic insecure protocols and risk associated with them: