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Compliant Solution (Windows)

The CryptGenRandomThe BCryptGenRandom() function function does not run the risk of not being properly seeded because its arguments serve as seeders:

Code Block

bgColor	#ccccff
lang	c

#include <stdio.h>
#include <Windows.h>
#include <wincrypt<Bcrypt.h>
#include <Ntstatus.h>
#include <stdio<Wincrypt.h>
 
void func(void) {
   HCRYPTPROV hCryptProvBCRYPT_ALG_HANDLE hAlgorithm = NULL;
  long rand_buf;
  /*PUCHAR ExamplepbBuffer of= instantiating the CSP */
  if (CryptAcquireContext(&hCryptProv, NULL, NULL,(PUCHAR) &rand_buf;
  ULONG cbBuffer                       PROV_RSA_FULL, 0)) {= sizeof(rand_buf);
  ULONG dwFlags printf("CryptAcquireContext succeeded.\n")= BCRYPT_USE_SYSTEM_PREFERRED_RNG;
  } else {
    printf("Error during CryptAcquireContext!\n")NTSTATUS status;
  }

  for (unsigned int i = 0; i < 10; ++i) {
    ifstatus = BCryptGenRandom(!CryptGenRandom(hCryptProvhAlgorithm, sizeof(rand_buf),
  pbBuffer, cbBuffer, dwFlags);
    if (status                 (BYTE *)&rand_buf))== STATUS_SUCCESS) {
      printf("Error\n"%ld, ", rand_buf);
    } else {
       printf("%ld, ", rand_buf);/* Handle Error */
    }
  }
}

The output is as follows:

Code Block

1st run: -1597837311683378946, 9061306821957231690, -13080318861933176011, 1048837407-1745403355, -931041900883473417, -658114613882992405, -1709220953169629816, -10196972891824800038, 1802206541899851668,
         406505841,1702784647, 
2nd run: 885904119-58750553, -6873795561921870721, -17822968541973269161, 14437019161512649964, -624291047673518452, 2049692692234003619, -9904515631622633366, 1312389688, -1423078042125631172, 12570792112067680022,
         897185104,
3rd run: 190598304-189899579, -15374094641220698973, 1594174739752205360, -4244019161826365616, -197515347479310867, 8269129271430950090, 1705549595-283206168, -1515331215941773185, 474951399129633665,
         1982500583,543448789,

Risk Assessment

Rule	Severity	Likelihood	Remediation Cost	Priority	Level
MSC32-C	Medium	Likely	Low	P18	L1

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Seeding routine uses a predictable seed making the output predictable

Seeding routine uses a constant seed making the output deterministic

CERT_C-MSC32-a-b
CERT_CMSC32-c
CERT_C-MSC32-Avoid functions which use random numbers from standard C library
Do not use the rand() function for generating pseudorandom numbersStandard random number generators should not be used to generate randomness for security reasons
9.1

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