diff --git a/boards/models/post/sync.py b/boards/models/post/sync.py
--- a/boards/models/post/sync.py
+++ b/boards/models/post/sync.py
@@ -1,4 +1,6 @@
 import xml.etree.ElementTree as et
+
+from boards.utils import get_file_mimetype
 from django.db import transaction
 from boards.models import KeyPair, GlobalId, Signature, Post, Tag
 
@@ -73,6 +75,21 @@ class SyncManager:
             pub_time = et.SubElement(content_tag, TAG_PUB_TIME)
             pub_time.text = str(post.get_pub_time_str())
 
+            images = post.images.all()
+            attachments = post.attachments.all()
+            if len(images) > 0 or len(attachments) > 0:
+                attachments_tag = et.SubElement(content_tag, TAG_ATTACHMENTS)
+                for image in images:
+                    mimetype = get_file_mimetype(image.image.file)
+                    attachment = et.SubElement(attachments_tag, TAG_ATTACHMENT)
+                    attachment.set(ATTR_MIMETYPE, mimetype)
+                    attachment.text = image.hash
+                for file in attachments:
+                    mimetype = get_file_mimetype(file.file.file)
+                    attachment = et.SubElement(attachments_tag, TAG_ATTACHMENT)
+                    attachment.set(ATTR_MIMETYPE, mimetype)
+                    attachment.text = file.hash
+
             signatures_tag = et.SubElement(model, TAG_SIGNATURES)
             post_signatures = post.global_id.signature_set.all()
             if post_signatures: