What a VPN Actually Protects You From (A Developer's Threat Model)

What a VPN Actually Protects You From (A Developer's Threat Model) Every "VPN explained" post reads like a sponsored ad. Let's do this properly — at the protocol level, with the actual threats mapped to the actual mitigations. TL;DR A VPN mitigates Layer 3/4 threats : passive ISP observation, Wi-Fi sniffing, IP-based geolocation, and some MITM scenarios on unencrypted endpoints. It does nothing against application-layer threats: malware, phishing, logged-in session tracking, browser fingerprinti