2 files changed, 6 insertions, 12 deletions
diff --git a/lib/pleroma/web/activity_pub/object_validators/attachment_validator.ex b/lib/pleroma/web/activity_pub/object_validators/attachment_validator.ex
index d1c61ac82..8b641d88d 100644
--- a/lib/pleroma/web/activity_pub/object_validators/attachment_validator.ex
+++ b/lib/pleroma/web/activity_pub/object_validators/attachment_validator.ex
@@ -12,14 +12,14 @@ defmodule Pleroma.Web.ActivityPub.ObjectValidators.AttachmentValidator do
   @primary_key false
   embedded_schema do
     field(:type, :string)
-    field(:mediaType, :string, default: "application/octet-stream")
+    field(:mediaType, ObjectValidators.MIME, default: "application/octet-stream")
     field(:name, :string)
     field(:blurhash, :string)
 
     embeds_many :url, UrlObjectValidator, primary_key: false do
       field(:type, :string)
       field(:href, ObjectValidators.Uri)
-      field(:mediaType, :string, default: "application/octet-stream")
+      field(:mediaType, ObjectValidators.MIME, default: "application/octet-stream")
       field(:width, :integer)
       field(:height, :integer)
     end
@@ -59,13 +59,7 @@ defmodule Pleroma.Web.ActivityPub.ObjectValidators.AttachmentValidator do
   end
 
   def fix_media_type(data) do
-    data = Map.put_new(data, "mediaType", data["mimeType"])
-
-    if is_bitstring(data["mediaType"]) && MIME.extensions(data["mediaType"]) != [] do
-      data
-    else
-      Map.put(data, "mediaType", "application/octet-stream")
-    end
+    Map.put_new(data, "mediaType", data["mimeType"])
   end
 
   defp handle_href(href, mediaType, data) do
diff --git a/lib/pleroma/web/activity_pub/transmogrifier.ex b/lib/pleroma/web/activity_pub/transmogrifier.ex
index a70330f0e..d6622df86 100644
--- a/lib/pleroma/web/activity_pub/transmogrifier.ex
+++ b/lib/pleroma/web/activity_pub/transmogrifier.ex
@@ -203,13 +203,13 @@ defmodule Pleroma.Web.ActivityPub.Transmogrifier do
 
         media_type =
           cond do
-            is_map(url) && MIME.extensions(url["mediaType"]) != [] ->
+            is_map(url) && url =~ Pleroma.Constants.mime_regex() ->
               url["mediaType"]
 
-            is_bitstring(data["mediaType"]) && MIME.extensions(data["mediaType"]) != [] ->
+            is_bitstring(data["mediaType"]) && data["mediaType"] =~ Pleroma.Constants.mime_regex() ->
               data["mediaType"]
 
-            is_bitstring(data["mimeType"]) && MIME.extensions(data["mimeType"]) != [] ->
+            is_bitstring(data["mimeType"]) && data["mimeType"] =~ Pleroma.Constants.mime_regex() ->
               data["mimeType"]
 
             true ->