Repeated NullRefs at ElectricWireController when using electric fence posts

Summary: When zombies walk into electric fence posts during the blood moon, the host’s console repeatedly opens to show a Null Reference Exception.

Game Version: A21.2 b37

OS/Version: macOS 10.14.6

CPU Model: Intel Core i9-9900K

System Memory: 40 GB

GPU Model and VRAM: AMD Radeon Pro Vega 48

Screen Resolution: 1920x1080

Video Settings: High

Game mode: Locally hosted multiplayer, RWG

Did you wipe old saves? No

Did you start a new game? No

Did you validate your files? No

Are you using any mods? No

EAC off

Status: NEW

Bug Description:

Detailed steps to reproduce the bug:

1) As the host of a multiplayer game, place six or so electric fence posts.

2) Connect the fence posts in series directly to a generator and power them up.

3) During a Blood Moon, allow zombies to hit the electric fence posts.

Actual result:

For the host, the console opens repeatedly - seemingly once every time a zombie connects with the fence - to report a Null Reference Exception:

NullReferenceException: Object reference not set to an instance of an object
  at ElectricWireController.DamageSelf (System.Single damage) [0x000dc] in <d0eae9af94fe45309fd53c292b4faa0e>:0 
  at ElectricWireController.touched (UnityEngine.Collider collider) [0x001a5] in <d0eae9af94fe45309fd53c292b4faa0e>:0 
  at ElectricWireController.Update () [0x000b2] in <d0eae9af94fe45309fd53c292b4faa0e>:0 

For other players, the game continues as normal.

Expected result:

Gameplay is not interrupted by console red text errors.

Log file: (excerpt in order to fit in pastebin)

https://pastebin.com/NAkDXQ70