The most secure software is open source, even old, underfunded open-source security projects can withstand the onslaught of exploits and invasions by the NSA. Open source has one main advantage over closed-source software: the code is public and can be inspected by anyone. The best way to use OpenVPN is through a well-established VPN service. Tor (or The Onion Router) is one of the leading and most reliable ways of browsing the internet without anyone following you online. The network routes your traffic through several relays, making it essentially impossible for someone to trace your identity.”]
Source: https://gbhackers.com/top-5-open-source-security-projects/