v4Guard Anti VPN

This version fixes a few specific scenarios that might be caused on edge cases.

We have fixed the following issues:

• Enforce case sensitive usernames. This avoid a edge case with our protection stack that was detected and reported by a customer.
• Proper invalidation of expired checks. This specific scenario can cause a memory leak if the backend was dropping your checks (for example, stability issues). And also, can be triggered by specific plugins that emulate logins. This was reported by a customer after their proxy crashed (while we were dropping his checks).
• Fallback timeout of pending kicks. This can be triggered if the user had set an invalid connect-timeout on their config. For example, less than 3 seconds, meaning that our async logic would be non operational.