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Cryptgenenandom entropy

CryptGenRandom is a random number generator feature in CryptoAPI on Windows. How much entropy does this random number generator have? I already watched a lot, but I could not find it. Thanks in advance.

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The exact Windows CryptGenRandom algorithm has never been published, so some security experts suggest not using it at all.

Some reverse engineering and cryptanalysis has been done. A published study ( Cryptanalysis of the Windows Random Number Generator - Leo Dorrendorf, 2007 ) examined the RNG of Windows 2000 and found a number of shortcomings in the design and implementation.

The document also describes the mechanism of the entropy collector of the algorithm (Section 4.2.3). Sources of entropy:

Source Bytes requested CircularHash 256 KSecDD 256 GetCurrentProcessID() 8 GetCurrentThreadID() 8 GetTickCount() 8 GetLocalTime() 16 QueryPerformanceCounter() 24 GlobalMemoryStatus() 16 GetDiskFreeSpace() 40 GetComputerName() 16 GetUserName() 257 GetCursorPos() 8 GetMessageTime() 16 NTQuerySystemInformation calls: ProcessorTimes 48 Performance 312 Exception 16 Lookaside 32 ProcessorStatistics up to the remaining length (3584 bytes buffer) ProcessesAndThreads up to the remaining length

Since we are talking about a pseudo-numerical generator and not a real number generator, you can say that there is no real entropy at all or consider only sources that you can consider as "entropy" (pseudo-entropy).

I could not find information about new versions in Windows.

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