[samuellavoie90]

Yes, if an hijacker got as far as the webcam, it's safe to assume they have access to everything else in your computer. But most webcams have a light to tell you if its being used, other dangers are keyloggers, and how they can be used to steal credit card information/bank loggin info.

[dsl]

The FBI (and most likely other actors) have the ability to activate a PC or Mac webcam without activating the light.

http://blog.erratasec.com/2013/12/how-to-disable-webcam-ligh...

[nitrogen]

But most webcams have a light to tell you if its being used...

Lights are frequently software controlled, as implied by the sibling comment to this one.

[tdicola]

It's actually possible to disable the light in a lot of cases, either by patching out the driver code or even reprogramming the camera firmware (in really extreme cases). Lots of info on practical examples from google: https://www.google.com/?gws_rd=ssl#q=disable+webcam+light

[zimbatm]

iSeeYou: Disabling the MacBook Webcam Indicator LED - https://jscholarship.library.jhu.edu/bitstream/handle/1774.2...