Jailbreak tool evasi0n7 has been promoted to version 1.0.4 to address a security issue and to include support for the upcoming iOS 7.1 from Apple.
Currently in internal testing, Apple’s iOS 7.1 is a few weeks (maybe even months) away from its public release, but that’s not stopping the evad3rs from adding it as a supported piece of firmware.
evasi0n7 version 1.0.4 comes with the following changes: “updated bundled Cydia, now double checking hfs modifications (for the iPad Mini Retina Cellular reboot loop issue), support for iOS 7.1beta3; security fix: kernel payload now restores sysent table; security fix: code fix for bootstrap Cydia tar files verification.”
You are to use these jailbreak tools at your own risk. Whatever you do, be sure to back up your device with iTunes first and foremost.