The Swiss Government has been testing surveillance software that could enable it to eavesdrop on voice over Internet Protocol (VoIP) communications.
According to Swiss newspaper SonntagsZeitung, police and intelligence services could could infect users' computers with this Trojan horse program and listen to their VoIP conversations. Any such move, though, would be subject to judicial approval.
The encryption used by VoIP communications such as Skype is easier to circumvent if investigators have access to the computers used to send the data, said SonntagsZeitung.
The VoIP-intercepting Trojan was developed by network security company ERA IT Solutions. Antivirus and firewalls don't currently recognise the program, which will send VoIP data from a user's PC to an external server. If a computer is turned off while data is still being gathered, the computer will save the data and retransmit once it is turned back on.
The Trojan can also reportedly activate built-in microphones in notebooks, which then allow listeners to pick up what is being talked about in the vicinity.
The Swiss Government kept the development of the software quiet to "avoid public discussion" of the issues. The project was led by the Swiss Department of the Environment, Transport, Energy and Communications.