Does anyone know what's causing this?

Assertion failed: (Index >= 0) & (Index < ArrayNum) [File:E:\ArkSVN-Trunk\Engine\Source\Runtime\Core\Public\Containers\Array.h] [Line: 572]
Array index out of bounds: -524288 from an array of size 25


VERSION: 304.32
KERNELBASE.dll!UnknownFunction (0x00007ffc7fada839) + 0 bytes [UnknownFile:0]
ShooterGame.exe!FOutputDevice::Logf__VA() (0x00007ff796b19178) + 159 bytes [e:\arksvn-trunk\engine\source\runtime\core\private\misc\outputdevice.cpp:145]
ShooterGame.exe!FDebug::AssertFailed() (0x00007ff796b19715) + 178 bytes [e:\arksvn-trunk\engine\source\runtime\core\private\misc\outputdevice.cpp:220]
ShooterGame.exe!FHierarchicalStaticMeshSceneProxy::OctreeTraverse_Recursive<1>() (0x00007ff79738cae9) + 88 bytes [e:\arksvn-trunk\engine\source\runtime\engine\private\hierarchicalinstancedstaticmesh.cpp:1523]
ShooterGame.exe!FHierarchicalStaticMeshSceneProxy::OctreeTraverse_Recursive<1>() (0x00007ff79738cdd0) + 49 bytes [e:\arksvn-trunk\engine\source\runtime\engine\private\hierarchicalinstancedstaticmesh.cpp:1567]
ShooterGame.exe!FHierarchicalStaticMeshSceneProxy::OctreeTraverse_Recursive<1>() (0x00007ff79738cdd0) + 49 bytes [e:\arksvn-trunk\engine\source\runtime\engine\private\hierarchicalinstancedstaticmesh.cpp:1567]
ShooterGame.exe!FHierarchicalStaticMeshSceneProxy::OctreeTraverse_Recursive<1>() (0x00007ff79738cdd0) + 49 bytes [e:\arksvn-trunk\engine\source\runtime\engine\private\hierarchicalinstancedstaticmesh.cpp:1567]
ShooterGame.exe!FHierarchicalStaticMeshSceneProxy::OctreeTraverse_Recursive<1>() (0x00007ff79738cdd0) + 49 bytes [e:\arksvn-trunk\engine\source\runtime\engine\private\hierarchicalinstancedstaticmesh.cpp:1567]
ShooterGame.exe!FHierarchicalStaticMeshSceneProxy::GetDynamicMeshElements() (0x00007ff797377637) + 0 bytes [e:\arksvn-trunk\engine\source\runtime\engine\private\hierarchicalinstancedstaticmesh.cpp:2211]
ShooterGame.exe!<lambda_b25d95720ec1b29ccdc7e8385483ec3b>::operator()() (0x00007ff798176b8e) + 0 bytes [e:\arksvn-trunk\engine\source\runtime\renderer\private\scenevisibility.cpp:2193]
ShooterGame.exe!FParallelForData::Process() (0x00007ff7972c0539) + 0 bytes [e:\arksvn-trunk\engine\source\runtime\core\public\async\parallelfor.h:124]
ShooterGame.exe!TGraphTask<FParallelForTask>::ExecuteTask() (0x00007ff7972dfa2a) + 16 bytes [e:\arksvn-trunk\engine\source\runtime\core\public\async\taskgraphinterfaces.h:871]
ShooterGame.exe!FTaskThreadAnyThread::ProcessTasks() (0x00007ff796a89016) + 0 bytes [e:\arksvn-trunk\engine\source\runtime\core\private\async\taskgraph.cpp:1257]
ShooterGame.exe!FTaskThreadAnyThread::ProcessTasksUntilQuit() (0x00007ff796a88d6e) + 0 bytes [e:\arksvn-trunk\engine\source\runtime\core\private\async\taskgraph.cpp:1150]
ShooterGame.exe!FTaskThreadBase::Run() (0x00007ff796a8782b) + 0 bytes [e:\arksvn-trunk\engine\source\runtime\core\private\async\taskgraph.cpp:622]
ShooterGame.exe!FRunnableThreadWin::Run() (0x00007ff796b6aac6) + 0 bytes [e:\arksvn-trunk\engine\source\runtime\core\private\windows\windowsrunnablethread.cpp:73]
ShooterGame.exe!FRunnableThreadWin::GuardedRun() (0x00007ff796b6a988) + 8 bytes [e:\arksvn-trunk\engine\source\runtime\core\private\windows\windowsrunnablethread.cpp:26]
KERNEL32.DLL!UnknownFunction (0x00007ffc80a07bd4) + 0 bytes [UnknownFile:0]
ntdll.dll!UnknownFunction (0x00007ffc81caced1) + 0 bytes [UnknownFile:0]
ntdll.dll!UnknownFunction (0x00007ffc81caced1) + 0 bytes [UnknownFile:0]

Crash in runnable thread TaskGraphThreadNP 1