What it is
ThinkPHP contains an unspecified vulnerability that allows for remote code execution via public//?s=index/\think\app/invokefunction&function=call_user_func_array&vars[0]=system&vars[1][]= followed by the command.
What to do
Apply updates per vendor instructions.
Vendor notices and references
Description and required action as published by CISA. Full record at NVD.