diff --git a/kotlin-native/runtime/src/custom_alloc/cpp/GCApi.cpp b/kotlin-native/runtime/src/custom_alloc/cpp/GCApi.cpp
index b4526779687..767c7f3bd62 100644
--- a/kotlin-native/runtime/src/custom_alloc/cpp/GCApi.cpp
+++ b/kotlin-native/runtime/src/custom_alloc/cpp/GCApi.cpp
@@ -38,7 +38,8 @@ bool SweepObject(uint8_t* object, FinalizerQueue& finalizerQueue, gc::GCHandle::
         gcHandle.addKeptObject();
         return true;
     }
-    auto* extraObject = mm::ExtraObjectData::Get(&objHeader->object);
+    auto* baseObject = &objHeader->object;
+    auto* extraObject = mm::ExtraObjectData::Get(baseObject);
     if (extraObject) {
         if (!extraObject->getFlag(mm::ExtraObjectData::FLAGS_IN_FINALIZER_QUEUE)) {
             CustomAllocDebug("SweepObject(%p): needs to be finalized, extraObject at %p", object, extraObject);
@@ -49,11 +50,13 @@ bool SweepObject(uint8_t* object, FinalizerQueue& finalizerQueue, gc::GCHandle::
             gcHandle.addMarkedObject();
             return true;
         }
-        if (!extraObject->getFlag(mm::ExtraObjectData::FLAGS_SWEEPABLE)) {
+        if (!extraObject->getFlag(mm::ExtraObjectData::FLAGS_FINALIZED)) {
             CustomAllocDebug("SweepObject(%p): already waiting to be finalized", object);
             gcHandle.addMarkedObject();
             return true;
         }
+        extraObject->UnlinkFromBaseObject();
+        extraObject->setFlag(mm::ExtraObjectData::FLAGS_SWEEPABLE);
     }
     CustomAllocDebug("SweepObject(%p): can be reclaimed", object);
     gcHandle.addSweptObject();
diff --git a/kotlin-native/runtime/src/mm/cpp/ExtraObjectData.cpp b/kotlin-native/runtime/src/mm/cpp/ExtraObjectData.cpp
index b2f70845d36..5e4d2332978 100644
--- a/kotlin-native/runtime/src/mm/cpp/ExtraObjectData.cpp
+++ b/kotlin-native/runtime/src/mm/cpp/ExtraObjectData.cpp
@@ -52,13 +52,15 @@ mm::ExtraObjectData& mm::ExtraObjectData::Install(ObjHeader* object) noexcept {
     return data;
 }
 
-void mm::ExtraObjectData::Uninstall() noexcept {
+void mm::ExtraObjectData::UnlinkFromBaseObject() noexcept {
     auto *object = GetBaseObject();
     atomicSetRelease(const_cast<const TypeInfo**>(&object->typeInfoOrMeta_), typeInfo_);
     RuntimeAssert(
             !object->has_meta_object(), "Object %p has metaobject %p after removing metaobject %p", object, object->meta_object_or_null(),
             this);
+}
 
+void mm::ExtraObjectData::ReleaseAssociatedObject() noexcept {
 #ifdef KONAN_OBJC_INTEROP
     if (void* associatedObject = associatedObject_) {
         if (getFlag(FLAGS_RELEASE_ON_MAIN_QUEUE) && isMainQueueProcessorAvailable()) {
@@ -73,6 +75,11 @@ void mm::ExtraObjectData::Uninstall() noexcept {
 #endif
 }
 
+void mm::ExtraObjectData::Uninstall() noexcept {
+    UnlinkFromBaseObject();
+    ReleaseAssociatedObject();
+}
+
 bool mm::ExtraObjectData::HasAssociatedObject() noexcept {
 #ifdef KONAN_OBJC_INTEROP
     return associatedObject_ != nullptr;
diff --git a/kotlin-native/runtime/src/mm/cpp/ExtraObjectData.hpp b/kotlin-native/runtime/src/mm/cpp/ExtraObjectData.hpp
index b5a36d01832..5118b14f17f 100644
--- a/kotlin-native/runtime/src/mm/cpp/ExtraObjectData.hpp
+++ b/kotlin-native/runtime/src/mm/cpp/ExtraObjectData.hpp
@@ -28,6 +28,7 @@ public:
         FLAGS_IN_FINALIZER_QUEUE = 2,
         FLAGS_SWEEPABLE = 3,
         FLAGS_RELEASE_ON_MAIN_QUEUE = 4,
+        FLAGS_FINALIZED = 5,
     };
 
     static constexpr unsigned WEAK_REF_TAG = 1;
@@ -43,11 +44,13 @@ public:
 
     static ExtraObjectData& Install(ObjHeader* object) noexcept;
     void Uninstall() noexcept;
+    void UnlinkFromBaseObject() noexcept;
 
 #ifdef KONAN_OBJC_INTEROP
     std::atomic<void*>& AssociatedObject() noexcept { return associatedObject_; }
 #endif
     bool HasAssociatedObject() noexcept;
+    void ReleaseAssociatedObject() noexcept;
 
     bool getFlag(Flags value) noexcept { return (flags_.load() & (1u << static_cast<uint32_t>(value))) != 0; }
     void setFlag(Flags value) noexcept { flags_.fetch_or(1u << static_cast<uint32_t>(value)); }
diff --git a/kotlin-native/runtime/src/mm/cpp/Memory.cpp b/kotlin-native/runtime/src/mm/cpp/Memory.cpp
index fb68843403e..388c8c8a9f0 100644
--- a/kotlin-native/runtime/src/mm/cpp/Memory.cpp
+++ b/kotlin-native/runtime/src/mm/cpp/Memory.cpp
@@ -78,10 +78,11 @@ MetaObjHeader* ObjHeader::createMetaObject(ObjHeader* object) {
 void ObjHeader::destroyMetaObject(ObjHeader* object) {
     RuntimeAssert(object->has_meta_object(), "Object must have a meta object set");
     auto &extraObject = *mm::ExtraObjectData::Get(object);
-    extraObject.Uninstall();
 #ifdef CUSTOM_ALLOCATOR
-    extraObject.setFlag(mm::ExtraObjectData::FLAGS_SWEEPABLE);
+    extraObject.ReleaseAssociatedObject();
+    extraObject.setFlag(mm::ExtraObjectData::FLAGS_FINALIZED);
 #else
+    extraObject.Uninstall();
     auto *threadData = mm::ThreadRegistry::Instance().CurrentThreadData();
     mm::ExtraObjectDataFactory::Instance().DestroyExtraObjectData(threadData, extraObject);
 #endif