diff --git a/js/src/ctypes/CTypes.cpp b/js/src/ctypes/CTypes.cpp
index 134175002b9d..130ea2327dad 100644
--- a/js/src/ctypes/CTypes.cpp
+++ b/js/src/ctypes/CTypes.cpp
@@ -5183,7 +5183,7 @@ CData::Finalize(JSContext* cx, JSObject* obj)
   char** buffer = static_cast<char**>(JSVAL_TO_PRIVATE(slot));
 
   if (owns)
-    delete *buffer;
+    delete[] *buffer;
   delete buffer;
 }