<p>Nodes don't propagate stale blocks.</p>
<p>However, blocks that are part of the heaviest chain are by definition not stale (anymore).</p>

CC BY-SA 4.0
2022-02-27T23:48:26.847Z
2022-02-27T23:48:26.847Z
Jannes
<p>I read somewhere (but can't find now) that while a node might receive a stale block, the node won't propagate a block that it knows to be stale. Is that true?</p>
<p>If so I don't quite understand how a secret attacking miner, even if they did unrealistically obtain &gt;51% hashing power, could pull off a massive reorg. I could see the attacker generating a fork with a longer chain, but when they tried to distribute that new chain to the network, they'd have to do it one block at a time. When a node received the first of the attackers new blocks, it would see it as a stale block, thus not propagate it, right?</p>

<stale-block>
Do nodes propagate stale blocks?
asdf
# Do nodes propagate stale blocks?

(Asked by: username_0 on 2022-02-27)

I read somewhere (but can't find now) that while a node might receive a stale block, the node won't propagate a block that it knows to be stale. Is that true?

If so I don't quite understand how a secret attacking miner, even if they did unrealistically obtain >51% hashing power, could pull off a massive reorg. I could see the attacker generating a fork with a longer chain, but when they tried to distribute that new chain to the network, they'd have to do it one block at a time. When a node received the first of the attackers new blocks, it would see it as a stale block, thus not propagate it, right?

**Tags:** stale-block


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## 1 answers

### Answer by username_1 on 2022-02-27. Score: 1

Nodes don't propagate stale blocks.

However, blocks that are part of the heaviest chain are by definition not stale (anymore).


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