diff --git a/models/activity/src/index.ts b/models/activity/src/index.ts
index 01c603b0c96..82b32c7fed9 100644
--- a/models/activity/src/index.ts
+++ b/models/activity/src/index.ts
@@ -279,6 +279,8 @@ export function createModel (builder: Builder): void {
   )
 
   builder.mixin(activity.class.Reaction, core.class.Class, core.mixin.TxAccessLevel, {
+    createAccessLevel: AccountRole.Guest,
+    updateAccessLevel: AccountRole.Guest,
     removeAccessLevel: AccountRole.Guest
   })
 
diff --git a/models/attachment/src/index.ts b/models/attachment/src/index.ts
index 8a0c8538938..f4adb00a120 100644
--- a/models/attachment/src/index.ts
+++ b/models/attachment/src/index.ts
@@ -22,7 +22,7 @@ import type {
   Photo,
   SavedAttachments
 } from '@hcengineering/attachment'
-import { IndexKind, type Blob, type Class, type Doc, type Domain, type Ref } from '@hcengineering/core'
+import { AccountRole, IndexKind, type Blob, type Class, type Doc, type Domain, type Ref } from '@hcengineering/core'
 import {
   Hidden,
   Index,
@@ -124,6 +124,10 @@ export function createModel (builder: Builder): void {
     editor: attachment.component.Attachments
   })
 
+  builder.mixin(attachment.class.Attachment, core.class.Class, core.mixin.TxAccessLevel, {
+    createAccessLevel: AccountRole.Guest
+  })
+
   builder.mixin(attachment.class.Photo, core.class.Class, view.mixin.CollectionEditor, {
     editor: attachment.component.Photos
   })