How does "nullping" attack work?

https://github.com/astei/krypton/blob/ebfd805dc6f2bbed7ce02e45d3d3b5e986ec8696/src/main/java/me/steinborn/krypton/mixin/shared/network/pipeline/SplitterHandlerMixin.java#L19

Can the decoder throw a cached exception instead of skip and ignore the 0x00 payload? Seems the current implementation ignores 0x00