diff --git a/src/modelTypes/ITask.ts b/src/modelTypes/ITask.ts
index bcbcf39253..8651e89eee 100644
--- a/src/modelTypes/ITask.ts
+++ b/src/modelTypes/ITask.ts
@@ -36,7 +36,7 @@ export interface ITask extends IAbstract {
 	percentDone: number
 	relatedTasks: Partial<Record<IRelationKind, ITask[]>>
 	attachments: IAttachment[]
-	coverImageAttachmentId: IAttachment['id']
+	coverImageAttachmentId: IAttachment['id'] | null
 	identifier: string
 	index: number
 	isFavorite: boolean
diff --git a/src/models/task.ts b/src/models/task.ts
index 03f419ddda..2499f97787 100644
--- a/src/models/task.ts
+++ b/src/models/task.ts
@@ -84,6 +84,7 @@ export default class TaskModel extends AbstractModel<ITask> implements ITask {
 	index = 0
 	isFavorite = false
 	subscription: ISubscription = null
+	coverImageAttachmentId: IAttachment['id'] = null
 
 	position = 0
 	kanbanPosition = 0