Soft U2F

This post introduces Soft U2F, a software-based U2F authenticator for macOS. It details the motivation for its development (low U2F adoption due to hardware requirements), the technical approach of emulating a HID device to communicate with browsers, and the storage of cryptographic keys in the macOS Keychain. It also discusses security considerations comparing hardware and software key storage, highlighting the trade-offs in terms of malware compromise duration.