diff --git a/libfreerdp/codec/test/TestFreeRDPCodecPlanar.c b/libfreerdp/codec/test/TestFreeRDPCodecPlanar.c
index 4f692df68..772665ec2 100644
--- a/libfreerdp/codec/test/TestFreeRDPCodecPlanar.c
+++ b/libfreerdp/codec/test/TestFreeRDPCodecPlanar.c
@@ -5757,7 +5757,7 @@ static BOOL FuzzPlanar(void)
 		       ", nDstHeight=%" PRIu32 ", nDstStep=%" PRIu32 ", total size=%" PRIuz "\n",
 		       FreeRDPGetColorFormatName(DstFormat), nXDst, nYDst, nDstWidth, nDstHeight, nDstStep,
 		       sizeof(dstData));
-		freerdp_planar_switch_bgr(planar, rand() % 2);
+		freerdp_planar_switch_bgr(planar, prand(2) % 2);
 		planar_decompress(planar, data, dataSize, prand(4096), prand(4096), dstData, DstFormat,
 		                  nDstStep, nXDst, nYDst, nDstWidth, nDstHeight, prand(2));
 	}
diff --git a/libfreerdp/gdi/test/TestGdiCreate.c b/libfreerdp/gdi/test/TestGdiCreate.c
index 01c113f81..4b042b561 100644
--- a/libfreerdp/gdi/test/TestGdiCreate.c
+++ b/libfreerdp/gdi/test/TestGdiCreate.c
@@ -7,6 +7,7 @@
 #include <freerdp/gdi/bitmap.h>
 
 #include <winpr/crt.h>
+#include <winpr/crypto.h>
 
 #include "line.h"
 #include "brush.h"
@@ -324,6 +325,13 @@ fail:
 	return rc;
 }
 
+static BYTE prand(void)
+{
+	BYTE tmp = 0;
+	winpr_RAND(&tmp, sizeof(tmp));
+	return tmp;
+}
+
 static BOOL test_gdi_GetPixel(void)
 {
 	BOOL rc = TRUE;
@@ -360,7 +368,7 @@ static BOOL test_gdi_GetPixel(void)
 			{
 				UINT32 pixel = 0;
 				const UINT32 color =
-				    FreeRDPGetColor(hBitmap->format, rand(), rand(), rand(), rand());
+				    FreeRDPGetColor(hBitmap->format, prand(), prand(), prand(), prand());
 				FreeRDPWriteColor(&hBitmap->data[i * hBitmap->scanline + j * bpp], hBitmap->format,
 				                  color);
 				pixel = gdi_GetPixel(hdc, j, i);
@@ -412,7 +420,7 @@ static BOOL test_gdi_SetPixel(void)
 			{
 				UINT32 pixel = 0;
 				const UINT32 color =
-				    FreeRDPGetColor(hBitmap->format, rand(), rand(), rand(), rand());
+				    FreeRDPGetColor(hBitmap->format, prand(), prand(), prand(), prand());
 				gdi_SetPixel(hdc, j, i, color);
 				pixel = FreeRDPReadColor(&hBitmap->data[i * hBitmap->scanline + j * bpp],
 				                         hBitmap->format);
diff --git a/libfreerdp/primitives/test/TestPrimitivesYUV.c b/libfreerdp/primitives/test/TestPrimitivesYUV.c
index c07d9d70f..5308b6b0c 100644
--- a/libfreerdp/primitives/test/TestPrimitivesYUV.c
+++ b/libfreerdp/primitives/test/TestPrimitivesYUV.c
@@ -687,6 +687,15 @@ static BOOL compare_yuv420(BYTE** planesA, BYTE** planesB, UINT32 width, UINT32
 	return rc;
 }
 
+static UINT32 prand(UINT32 max)
+{
+	UINT32 tmp = 0;
+	if (max <= 1)
+		return 1;
+	winpr_RAND(&tmp, sizeof(tmp));
+	return tmp % (max - 1) + 1;
+}
+
 static BOOL TestPrimitiveRgbToLumaChroma(primitives_t* prims, prim_size_t roi, UINT32 version)
 {
 	BOOL res = FALSE;
@@ -772,10 +781,10 @@ static BOOL TestPrimitiveRgbToLumaChroma(primitives_t* prims, prim_size_t roi, U
 		for (UINT32 x = 0; x < roi.width; x++)
 		{
 #if 1
-			line[x * 4 + 0] = rand();
-			line[x * 4 + 1] = rand();
-			line[x * 4 + 2] = rand();
-			line[x * 4 + 3] = rand();
+			line[x * 4 + 0] = prand(UINT8_MAX);
+			line[x * 4 + 1] = prand(UINT8_MAX);
+			line[x * 4 + 2] = prand(UINT8_MAX);
+			line[x * 4 + 3] = prand(UINT8_MAX);
 #else
 			line[x * 4 + 0] = (y * roi.width + x) * 16 + 5;
 			line[x * 4 + 1] = (y * roi.width + x) * 16 + 7;
diff --git a/winpr/libwinpr/error/test/TestErrorSetLastError.c b/winpr/libwinpr/error/test/TestErrorSetLastError.c
index a3d57af02..cb1ad87c6 100644
--- a/winpr/libwinpr/error/test/TestErrorSetLastError.c
+++ b/winpr/libwinpr/error/test/TestErrorSetLastError.c
@@ -19,6 +19,7 @@
  */
 
 #include <winpr/crt.h>
+#include <winpr/crypto.h>
 #include <winpr/wlog.h>
 #include <winpr/synch.h>
 #include <winpr/thread.h>
@@ -31,6 +32,15 @@ static int status = 0;
 static LONG* pLoopCount = NULL;
 static BOOL bStopTest = FALSE;
 
+static UINT32 prand(UINT32 max)
+{
+	UINT32 tmp = 0;
+	if (max <= 1)
+		return 1;
+	winpr_RAND(&tmp, sizeof(tmp));
+	return tmp % (max - 1) + 1;
+}
+
 static DWORD WINAPI test_error_thread(LPVOID arg)
 {
 	int id = 0;
@@ -41,7 +51,7 @@ static DWORD WINAPI test_error_thread(LPVOID arg)
 
 	do
 	{
-		dwErrorSet = (DWORD)abs(rand()) + 1;
+		dwErrorSet = prand(UINT32_MAX - 1) + 1;
 		SetLastError(dwErrorSet);
 		if ((dwErrorGet = GetLastError()) != dwErrorSet)
 		{
diff --git a/winpr/libwinpr/path/test/TestPathMakePath.c b/winpr/libwinpr/path/test/TestPathMakePath.c
index af4f3fff1..36fbaaf05 100644
--- a/winpr/libwinpr/path/test/TestPathMakePath.c
+++ b/winpr/libwinpr/path/test/TestPathMakePath.c
@@ -3,9 +3,19 @@
 #include <time.h>
 
 #include <winpr/crt.h>
+#include <winpr/crypto.h>
 #include <winpr/file.h>
 #include <winpr/path.h>
 
+static UINT32 prand(UINT32 max)
+{
+	UINT32 tmp = 0;
+	if (max <= 1)
+		return 1;
+	winpr_RAND(&tmp, sizeof(tmp));
+	return tmp % (max - 1) + 1;
+}
+
 int TestPathMakePath(int argc, char* argv[])
 {
 	size_t baseLen = 0;
@@ -26,11 +36,10 @@ int TestPathMakePath(int argc, char* argv[])
 	}
 
 	baseLen = strlen(base);
-	srand(time(NULL));
 
 	for (int x = 0; x < 5; x++)
 	{
-		(void)sprintf_s(tmp, ARRAYSIZE(tmp), "%08X", rand());
+		(void)sprintf_s(tmp, ARRAYSIZE(tmp), "%08" PRIX32, prand(UINT32_MAX));
 		path = GetCombinedPath(base, tmp);
 		free(base);
 
diff --git a/winpr/libwinpr/synch/test/TestSynchBarrier.c b/winpr/libwinpr/synch/test/TestSynchBarrier.c
index 5bca01964..bbbc99310 100644
--- a/winpr/libwinpr/synch/test/TestSynchBarrier.c
+++ b/winpr/libwinpr/synch/test/TestSynchBarrier.c
@@ -1,5 +1,6 @@
 
 #include <winpr/crt.h>
+#include <winpr/crypto.h>
 #include <winpr/synch.h>
 #include <winpr/thread.h>
 #include <winpr/interlocked.h>
@@ -22,6 +23,15 @@ struct test_params
 	DWORD flags;
 };
 
+static UINT32 prand(UINT32 max)
+{
+	UINT32 tmp = 0;
+	if (max <= 1)
+		return 1;
+	winpr_RAND(&tmp, sizeof(tmp));
+	return tmp % (max - 1) + 1;
+}
+
 static DWORD WINAPI test_synch_barrier_thread(LPVOID lpParam)
 {
 	BOOL status = FALSE;
@@ -43,7 +53,7 @@ static DWORD WINAPI test_synch_barrier_thread(LPVOID lpParam)
 	for (DWORD i = 0; i < p->loops && gErrorCount == 0; i++)
 	{
 		/* simulate different execution times before the barrier */
-		Sleep(1 + abs((rand() % MAX_SLEEP_MS)));
+		Sleep(1 + prand(MAX_SLEEP_MS));
 		status = EnterSynchronizationBarrier(&gBarrier, p->flags);
 
 		// printf("Thread #%03u status: %s\n", tnum, status ? "TRUE" : "FALSE");
diff --git a/winpr/libwinpr/synch/test/TestSynchCritical.c b/winpr/libwinpr/synch/test/TestSynchCritical.c
index d78e01cf7..800622ff5 100644
--- a/winpr/libwinpr/synch/test/TestSynchCritical.c
+++ b/winpr/libwinpr/synch/test/TestSynchCritical.c
@@ -1,6 +1,7 @@
 
 #include <stdio.h>
 #include <winpr/crt.h>
+#include <winpr/crypto.h>
 #include <winpr/windows.h>
 #include <winpr/synch.h>
 #include <winpr/sysinfo.h>
@@ -40,6 +41,15 @@ static BOOL TestSynchCritical_TriggerAndCheckRaceCondition(HANDLE OwningThread,
 	return TRUE;
 }
 
+static UINT32 prand(UINT32 max)
+{
+	UINT32 tmp = 0;
+	if (max <= 1)
+		return 1;
+	winpr_RAND(&tmp, sizeof(tmp));
+	return tmp % (max - 1) + 1;
+}
+
 /* this thread function shall increment the global dwTestValue until the PBOOL passsed in arg is
  * FALSE */
 static DWORD WINAPI TestSynchCritical_Test1(LPVOID arg)
@@ -59,14 +69,14 @@ static DWORD WINAPI TestSynchCritical_Test1(LPVOID arg)
 			return 1;
 
 		/* add some random recursion level */
-		int j = rand() % 5;
-		for (int i = 0; i < j; i++)
+		UINT32 j = prand(5);
+		for (UINT32 i = 0; i < j; i++)
 		{
 			if (!TestSynchCritical_TriggerAndCheckRaceCondition(hThread, rc++))
 				return 2;
 			EnterCriticalSection(&critical);
 		}
-		for (int i = 0; i < j; i++)
+		for (UINT32 i = 0; i < j; i++)
 		{
 			if (!TestSynchCritical_TriggerAndCheckRaceCondition(hThread, rc--))
 				return 2;
diff --git a/winpr/libwinpr/synch/test/TestSynchInit.c b/winpr/libwinpr/synch/test/TestSynchInit.c
index 582a5cdf4..2baee47a9 100644
--- a/winpr/libwinpr/synch/test/TestSynchInit.c
+++ b/winpr/libwinpr/synch/test/TestSynchInit.c
@@ -1,5 +1,6 @@
 #include <stdio.h>
 #include <winpr/crt.h>
+#include <winpr/crypto.h>
 #include <winpr/synch.h>
 #include <winpr/thread.h>
 #include <winpr/interlocked.h>
@@ -15,6 +16,15 @@ static LONG* pTestThreadFunctionCalls = NULL;
 static LONG* pTestOnceFunctionCalls = NULL;
 static LONG* pInitOnceExecuteOnceCalls = NULL;
 
+static UINT32 prand(UINT32 max)
+{
+	UINT32 tmp = 0;
+	if (max <= 1)
+		return 1;
+	winpr_RAND(&tmp, sizeof(tmp));
+	return tmp % (max - 1) + 1;
+}
+
 static BOOL CALLBACK TestOnceFunction(PINIT_ONCE once, PVOID param, PVOID* context)
 {
 	LONG calls = InterlockedIncrement(pTestOnceFunctionCalls) - 1;
@@ -24,7 +34,7 @@ static BOOL CALLBACK TestOnceFunction(PINIT_ONCE once, PVOID param, PVOID* conte
 	WINPR_UNUSED(context);
 
 	/* simulate execution time */
-	Sleep(30 + rand() % 40);
+	Sleep(30 + prand(40));
 
 	if (calls < TEST_NUM_FAILURES)
 	{
diff --git a/winpr/libwinpr/synch/test/TestSynchMultipleThreads.c b/winpr/libwinpr/synch/test/TestSynchMultipleThreads.c
index 7218b6482..34820f148 100644
--- a/winpr/libwinpr/synch/test/TestSynchMultipleThreads.c
+++ b/winpr/libwinpr/synch/test/TestSynchMultipleThreads.c
@@ -2,14 +2,24 @@
 #include <stdlib.h>
 
 #include <winpr/crt.h>
+#include <winpr/crypto.h>
 #include <winpr/synch.h>
 #include <winpr/thread.h>
 
 #define THREADS 8
 
+static UINT32 prand(UINT32 max)
+{
+	UINT32 tmp = 0;
+	if (max <= 1)
+		return 1;
+	winpr_RAND(&tmp, sizeof(tmp));
+	return tmp % (max - 1) + 1;
+}
+
 static DWORD WINAPI test_thread(LPVOID arg)
 {
-	long timeout = 50 + (rand() % 100);
+	UINT32 timeout = 50 + prand(100);
 	WINPR_UNUSED(arg);
 	Sleep(timeout);
 	ExitThread(0);