Destroying a welded actor is causing an Array index out of bounds crash on 5.6

UE - Simulation - Physics - Jul 30, 2025

Destroying a welded actor is causing an Array index out of bounds crash on 5.6. The licensee has provided a repro project that reliably causes a crash whenever the spawned actor is destroyed. There ...

Editor added components can fail to attach to a native root component

UE - Framework - Blueprint - Feb 8, 2021

An actor instance's editor added components can fail to attach to the root component of the actor when changing the native root component's mobility from static to movable. The failure happens durin ...

Crash when opening a new level while opening Editor Utility Widget after opening and closing it multiple times

Tools - Jun 4, 2019

Crash when opening a new level with reopened EditorUtilityWidget after opening and closing it multiple times. The cause of this issue is that UEditorUtilityWidgetBlueprint :: UpdateRespawnListIfNee ...

HLOD Build crashing when building nanite for mesh with 2 material having the same parameters

UE - World Creation - Worldbuilding Tools - HLOD - Dec 2, 2023

From Licensee: Catching the exception with debugger allowed us to find a list of materials on the hlod mesh on which the error occured and we were then able to link it to one of our meshes causing ...

Crash on hot reload for DynamicDelegate

UE - Foundation - Core - Mar 23, 2020

This issue may be badly implemented, but the reference to the VTable may be incorrect during a hot reload. Crash always in sample project. Summary:Call ForeachRow function in Custom Struct constr ...

Calling ServerTravel with bShouldSkipGameNotify set to false causes a crash

UE - Gameplay - Feb 22, 2019

Calling ServerTravel with bShouldSkipGameNotify set to false results in a crash. The reproduction case provided is in PIE but this also occurs in a packaged game Regression?: Yes This did not occur ...

Crash when using Get Start/End Frame (Seconds) node with MovieSceneSection have no opened bound

UE - Anim - Sequencer - Aug 14, 2019

If use Get Start/End Frame (Seconds) with GetStartFrame has a section isBounded is False, eg 3DTransformSection, editor will be crashed. Specifically, a following code occur crash. inline FFrame ...

Launch crashes on Android if device has Wifi disconnected

UE - Platform - Mobile - Mar 10, 2016

Launch On crashes on a Android devices if networking is disabled. This used to work and should not crash. ...

During SIE (simulate) and ejected-PIE, modifying a map actor causes triggers RerunConstructionScript() which discards all runtime modifications to SCS components

UE - Framework - Blueprint Runtime - Sep 6, 2024

When Simulating, or Playing-In-Editor and ejected, modifying an actor in the editor world causes the SIE/PIE runtime actor to recreate its blueprint added components via AActor::RerunConstructionScr ...

Crash when the location of actor changes while executing SetAnimInstanceClass

OLD - Anim - May 27, 2019

This issue doesn't occur at 4.21. It seems in 4.22 only. Bone is broken in the second SetAnimInstanceClass. It seems CurrentReadComponentTransforms doesn't update. [Workaround] ・Wait using timer ...