Little Snitch 5 for macOS Big Sur
The previous version 4 of Little Snitch intercepted network traffic by means of a Network Kernel Extension. This type of kernel extension is deprecated in macOS Big Sur and no longer loads in the default configuration.
Little Snitch 5 is based on the new Network Extension framework instead, which is fully supported on macOS Big Sur.
Learn more what’s new in Little Snitch 5
If you have purchased Little Snitch 4 after November 1, 2019, you can upgrade to Little Snitch 5 for free – just use your existing license key. If you purchased Little Snitch 4 before that period, you can get the upgrade at a reduced price.