There’s a bug in macOS Ventura causing “Full Disk Access” sometimes to fail to work properly. As a result, “Full Disk Access” for the “Little Snitch Endpoint Security” system extension cannot be granted or is lost on every restart.
Until this is fixed in a newer version of macOS, you can manually resolve the issue as follows:
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Open “System Settings”, click on “Privacy & Security”, and navigate to “Full Disk Access.”
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Right-click the “Little Snitch Endpoint Security” item and choose “Show in Finder.”
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With the newly opened Finder window kept open, switch back to “System Settings.”
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Left-click the “Little Snitch Endpoint Security” item in the list to select it.
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Remove it by clicking the (–) minus button at the bottom of the list.
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Switch back to the Finder window displaying an item named “Little Snitch Endpoint Security” (there may be other items).
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Select the “Little Snitch Endpoint Security” item and drag and drop it onto the “Full Disk Access” list in “System Settings.”