diff --git a/firmware_handler.cpp b/firmware_handler.cpp
index f6344d1..6e64d9d 100644
--- a/firmware_handler.cpp
+++ b/firmware_handler.cpp
@@ -482,10 +482,9 @@
         return false;
     }
 
-    /* Prevent writing to the verification blob before they trigger
-     * verification.
-     */
-    if (item->second->activePath == verifyBlobId)
+    /* Prevent writing to the verification or update blobs. */
+    if (item->second->activePath == verifyBlobId ||
+        item->second->activePath == updateBlobId)
     {
         return false;
     }