Question : Two Networks - Two NICS - Security?

I have two separate networks in our business.  Due to limited resources, I can only have a single computer at a few workstations that require the use of applications that reside on each separate network.  I put two NICS into the computer, setup with different TCP/IP and MASK.  It is working fine, BUT, my concern now is secuirty.  Did I just, for lack of a better term, bridge them together?  How can I make sure I didn't just compromise the networks?  If the single computer gets a virus, can it give it to both network?

Answer : Two Networks - Two NICS - Security?

I agree with the other expert, unless you have specifically created a bridge I don't think you have actually bridged them. Having said that, I don't know that this means you have security against some kind of malware infection. My guess is that in order to make use of both connections on one PC, you have had to do something in the routing table of the PC. And even if not, at least both connections are available on that PC. Malware may be able to make use of both connections just like your applications can. So, the other experts other statement is also true, be vigilant and make sure that you have the proper protections in place. Not sure that the likelihood of an infection spreading from network to network is likely, but I wouldn't say that it's impossible