Hi [there]
I prefer do not state nothing about if TV is good or not good, but, I can share my personal experience:
I received the same question from the same kind of professional, many months ago. But, I was unable to get something useful the first time.
Many months after, when analyzed by network traffic I unveiled a complete TCP session with another computer in our same broadband
neighborhood, (initiated) from my system, by using the same protocol that TeamViewer use. [I had installed TV to support a customer, and TV was turn on in my computer]
What? I was more than worry (this was a terrific experience), as you can imaging. So, I asked myself: When I connected to this other computer, this IP doesn’t belong to the company’s IP range where I connected before? (As you know TeamViewer doesn’t connect from IP to IP [they use a central as you quoted]).
The packets were very little (but there were completed tcp sessions), to looks like an intrusion. But, It was not so enough to me.
I made a little research on that, and that IP didn’t belong to TeamViewer network. (with some little tricks, I determined) That specific IP address belonged to a company, which didn’t sell TeamViewer software. I made some calls to be sure if this IP address does belong to TeamViewer network.
After, no positive evidence, I wrote to TeamViewer.
And after many emails with one TeamViewer’s security specialist, they never answered me why there were using as a TeamViewer gateway an IP address out of the TeamViewer’s IP block. Actually, she confirmed that the connection was a keep alive with the TeamViewer gateways’ network.
So, I conclude, that if I go to use TV (as a support guy), I must turn off the service after use it, or my computer will send complete tcp
connections with some stranges gateways around you, which, probably are not part of the TeamViewer’s IP block. So, by reading risk between lines: if your Bank customer is in the same IP network block of its competitor (who knows about this little experience) you can be sure that they (the competitor) will enjoy to learn that your customer is using TeamViewer =) [probably as a TV permanently ON]
PD: if you have time, run you own test, and see, if this behaviour still exists and comment on me, please.
JaCkSecurity, CTO
Conocimiento, Conciencia y Consultoría