diff --git a/src/fuzzers/D3D12Fuzzer.cpp b/src/fuzzers/D3D12Fuzzer.cpp
index 329c0f0f6..a96a85915 100644
--- a/src/fuzzers/D3D12Fuzzer.cpp
+++ b/src/fuzzers/D3D12Fuzzer.cpp
@@ -16,7 +16,7 @@
 
 uint64_t UInt8ToUInt64(const uint8_t* src) {
     uint64_t dst;
-    memcpy(&dst, src, sizeof(uint64_t));
+    memcpy_s(&dst, sizeof(uint64_t), src, sizeof(uint8_t));
     return dst;
 }
 
diff --git a/src/gpgmm/d3d12/ResourceAllocatorD3D12.cpp b/src/gpgmm/d3d12/ResourceAllocatorD3D12.cpp
index 6241a155b..8e6f92dc3 100644
--- a/src/gpgmm/d3d12/ResourceAllocatorD3D12.cpp
+++ b/src/gpgmm/d3d12/ResourceAllocatorD3D12.cpp
@@ -1461,7 +1461,8 @@ namespace gpgmm::d3d12 {
                 }
                 data.IsResourceAllocationWithinCoherent =
                     mCaps->IsResourceAllocationWithinCoherent();
-                memcpy(pFeatureSupportData, &data, featureSupportDataSize);
+                memcpy_s(pFeatureSupportData, sizeof(pFeatureSupportData), &data,
+                         featureSupportDataSize);
                 return S_OK;
             }
             default: {
diff --git a/src/tests/end2end/D3D12ResourceAllocatorTests.cpp b/src/tests/end2end/D3D12ResourceAllocatorTests.cpp
index fb576a677..073aa3854 100644
--- a/src/tests/end2end/D3D12ResourceAllocatorTests.cpp
+++ b/src/tests/end2end/D3D12ResourceAllocatorTests.cpp
@@ -1166,21 +1166,21 @@ TEST_F(D3D12ResourceAllocatorTests, CreateBufferWithinMany) {
                                 0xCC);
     void* mappedBufferC = nullptr;
     ASSERT_SUCCEEDED(smallBufferC->Map(/*subresource*/ 0, nullptr, &mappedBufferC));
-    memcpy(mappedBufferC, dataCC.data(), dataCC.size());
+    memcpy_s(mappedBufferC, smallBufferC->GetInfo().SizeInBytes, dataCC.data(), dataCC.size());
 
     // Fill small buffer A with value 0xAA.
     std::vector<uint8_t> dataAA(static_cast<const size_t>(smallBufferA->GetInfo().SizeInBytes),
                                 0xAA);
     void* mappedBufferA = nullptr;
     ASSERT_SUCCEEDED(smallBufferA->Map(/*subresource*/ 0, nullptr, &mappedBufferA));
-    memcpy(mappedBufferA, dataAA.data(), dataAA.size());
+    memcpy_s(mappedBufferA, smallBufferA->GetInfo().SizeInBytes, dataAA.data(), dataAA.size());
 
     // Fill small buffer B with value 0xBB.
     std::vector<uint8_t> dataBB(static_cast<const size_t>(smallBufferB->GetInfo().SizeInBytes),
                                 0xBB);
     void* mappedBufferB = nullptr;
     ASSERT_SUCCEEDED(smallBufferB->Map(/*subresource*/ 0, nullptr, &mappedBufferB));
-    memcpy(mappedBufferB, dataBB.data(), dataBB.size());
+    memcpy_s(mappedBufferB, smallBufferB->GetInfo().SizeInBytes, dataBB.data(), dataBB.size());
 
     EXPECT_NE(mappedBufferA, mappedBufferB);
     EXPECT_NE(mappedBufferB, mappedBufferC);