An issue was discovered in BlueStacks 4.110 and below on macOS and on 4.120 and below on Windows. BlueStacks employs Android running in a virtual machine (VM) to enable Android apps to run on Windows or MacOS. Bug is in a local arbitrary file read through a system service call. The impacted method runs with System admin privilege and if given the file name as parameter returns you the content of file. A malicious app using the affected method can then read the content of any system file which it is not authorized to read
https://support.bluestacks.com/hc/en-us/articles/360021469391-Release-Notes