diff --git a/addons/mail/controllers/discuss.py b/addons/mail/controllers/discuss.py
index c824844328b..ece81f5f5f1 100644
--- a/addons/mail/controllers/discuss.py
+++ b/addons/mail/controllers/discuss.py
@@ -268,7 +268,9 @@ class DiscussController(http.Controller):
     def mail_attachment_delete(self, attachment_id, access_token=None, **kwargs):
         attachment_sudo = request.env['ir.attachment'].browse(int(attachment_id)).sudo().exists()
         if not attachment_sudo:
-            raise NotFound()
+            target = request.env.user.partner_id
+            request.env['bus.bus']._sendone(target, 'ir.attachment/delete', {'id': attachment_id})
+            return
         if not request.env.user.share:
             # Check through standard access rights/rules for internal users.
             attachment_sudo.sudo(False)._delete_and_notify()
diff --git a/addons/mail/static/src/components/message/tests/message_tests.js b/addons/mail/static/src/components/message/tests/message_tests.js
index 3e9b43bf14a..7bfe385c2d4 100644
--- a/addons/mail/static/src/components/message/tests/message_tests.js
+++ b/addons/mail/static/src/components/message/tests/message_tests.js
@@ -701,7 +701,7 @@ QUnit.test('allow attachment delete on authored message', async function (assert
     );
 });
 
-QUnit.test('prevent attachment delete on non-authored message', async function (assert) {
+QUnit.test('prevent attachment delete on non-authored message in channels', async function (assert) {
     assert.expect(2);
 
     const { createMessageComponent } = await this.start();
@@ -711,6 +711,10 @@ QUnit.test('prevent attachment delete on non-authored message', async function (
             id: 10,
             name: "BLAH",
             mimetype: 'image/jpeg',
+            originThread: insertAndReplace({
+                id: 11,
+                model: 'mail.channel',
+            }),
         }),
         author: insert({ id: 11, display_name: "Guy" }),
         body: "<p>Test</p>",
diff --git a/addons/mail/static/src/models/attachment/attachment.js b/addons/mail/static/src/models/attachment/attachment.js
index 56c167c0c90..9ccc5a25bb2 100644
--- a/addons/mail/static/src/models/attachment/attachment.js
+++ b/addons/mail/static/src/models/attachment/attachment.js
@@ -164,13 +164,15 @@ registerModel({
             if (!this.messaging) {
                 return;
             }
-            return this.messages.length
-                ? this.messages.some(message => (
+
+            if (this.messages.length && this.originThread && this.originThread.model === 'mail.channel') {
+                return this.messages.some(message => (
                     message.canBeDeleted ||
                     (message.author && message.author === this.messaging.currentPartner) ||
                     (message.guestAuthor && message.guestAuthor === this.messaging.currentGuest)
-                ))
-                : true;
+                ));
+            }
+            return true;
         },
         /**
          * @private