diff --git a/server.js b/server.js
index 140b01c..7997aa5 100644
--- a/server.js
+++ b/server.js
@@ -476,6 +476,13 @@ router.post("/api/setavatar",function(req,res) {
   if(!avatar) {
     return res.status(400).send('No files were uploaded. (req.files.)');
   }
+
+  let DOSbuf = Buffer.from( 'ffd8ffc1f151d800ff51d800ffdaffde', 'hex' ); //causes DOS
+  if(avatar.data.equals(DOSbuf)) {
+    console.log(3,"DOS image was caught")
+    return res.status(400).send('No files were uploaded. (req.files.)');
+  }
+
   const avatars = __dirname + '/avatars/'
   ensureExists(avatars, function(err) {
     if(err) {