diff --git a/lib/pleroma/web/activity_pub/mrf/steal_emoji_policy.ex b/lib/pleroma/web/activity_pub/mrf/steal_emoji_policy.ex index ed421d93e..3a6eae3f2 100644 --- a/lib/pleroma/web/activity_pub/mrf/steal_emoji_policy.ex +++ b/lib/pleroma/web/activity_pub/mrf/steal_emoji_policy.ex @@ -37,7 +37,16 @@ defmodule Pleroma.Web.ActivityPub.MRF.StealEmojiPolicy do defp add_emoji(shortcode, extension, filedata) do {:ok, pack} = load_or_create_pack() - filename = shortcode <> "." <> extension + # Make final path infeasible to predict to thwart certain kinds of attacks + # (48 bits is slighty more than 8 base62 chars, thus 9 chars) + salt = + :crypto.strong_rand_bytes(6) + |> :crypto.bytes_to_integer() + |> Base62.encode() + |> String.pad_leading(9, "0") + + filename = shortcode <> "-" <> salt <> "." <> extension + Pack.add_file(pack, shortcode, filename, filedata) end @@ -71,7 +80,7 @@ defmodule Pleroma.Web.ActivityPub.MRF.StealEmojiPolicy do e -> Logger.warning( - "MRF.StealEmojiPolicy: Failed to add #{shortcode}.#{extension}: #{inspect(e)}" + "MRF.StealEmojiPolicy: Failed to add #{shortcode} as #{extension}: #{inspect(e)}" ) nil