Selfish mining is a strategy where a miner withholds discovered blocks to gain an unfair advantage and earn more rewards than their share of total hash power. In traditional blockchains like Bitcoin, selfish mining becomes profitable at around 33% hash power, and under certain propagation advantages even lower.
Kaspa, however, is significantly more resistant to selfish mining because of its BlockDAG structure, GHOSTDAG consensus, and multi-block parallelism. These features make withholding blocks far less effective — and often counterproductive.
Here’s why Kaspa is much harder to exploit through selfish mining than classical blockchains.
1. Kaspa Accepts All Blocks — Making Withholding Less Effective
In Bitcoin, withholding a block temporarily can:
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create a secret chain
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surprise the network with a longer chain
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override honest miners
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steal mining rewards
Kaspa does not operate this way.
✔ Kaspa accepts all valid blocks into the DAG.
✔ Competing blocks do NOT become orphans.
✔ Withholding blocks does NOT automatically create profit.
This single design choice removes the core incentive behind selfish mining.
2. GHOSTDAG Makes “Secret Chains” Impossible
Bitcoin’s selfish mining relies on building a secret alternate chain that later overtakes the honest chain.
Kaspa’s GHOSTDAG prevents this tactic from being effective because:
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the DAG structure has no single “main chain”
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the priority (blue set) is chosen by connectivity
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blocks hidden from the network are less connected
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late-revealed blocks become red, not blue
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red blocks have lower consensus weight
✔ Hidden blocks are downgraded — not rewarded.
A selfish miner loses ordering priority by withholding blocks, destroying the attack’s profitability.
3. Blue Score Punishes Withholding
Kaspa ranks blocks by blue score, which measures how well a block fits into the honest, well-propagated part of the DAG.
When an attacker withholds blocks:
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those blocks miss connections to other honest blocks
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they accumulate fewer blue ancestors
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their blue score becomes significantly lower
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the attacker’s chain is deprioritized
The result:
Hidden blocks become less valuable than honest blocks.
This flips the selfish mining strategy on its head.
4. High Block Rate Reduces the Attacker’s Advantage
Kaspa produces multiple blocks per second, which means:
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honest miners add new blocks too quickly
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an attacker’s private chain gets buried
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connectivity gaps grow rapidly
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stale DAG branches become disadvantaged
In Bitcoin, producing one block can give the attacker a temporary lead.
In Kaspa, the network moves too fast for this to matter.
✔ Speed works against the attacker.
5. Propagation Advantages Don’t Matter as Much
In Bitcoin, miners near each other geographically can propagate blocks faster, gaining an edge.
Kaspa eliminates most propagation advantage because:
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many blocks are accepted in parallel
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there is no “race” to be the single next block
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late-arriving blocks still get included
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GHOSTDAG ordering ignores arrival time
Selfish miners can’t exploit latency differences when timing has minimal effect on consensus.
6. Consensus Finality Is Built on Connectivity, Not Timing
Bitcoin’s longest-chain rule makes timing incredibly important.
Kaspa’s DAG makes structure, not timing, the deciding factor.
Selfish mining depends on:
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beating the network to publication
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forcing honest miners to waste work
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orphaning others’ blocks
Kaspa removes all three incentives.
7. Profitability Threshold Is Significantly Higher Than Bitcoin
While the exact threshold depends on propagation patterns and the configured K-parameter of GHOSTDAG, Kaspa’s design makes selfish mining:
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unprofitable for small attackers
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unprofitable for mid-sized attackers
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extremely difficult even with one-third of total hashrate
The effective attack threshold is believed to be much higher than Bitcoin’s 33%, because withheld blocks lose blue score and become low-priority.
Conclusion
Kaspa is highly resistant to selfish mining thanks to:
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BlockDAG parallelism
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GHOSTDAG ordering
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blue/red block classification
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blue score penalties for withheld blocks
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lack of orphan races
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high block rate
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structure-over-timing consensus
Withholding blocks results in reduced rewards, not increased ones — making classical selfish mining strategies ineffective.
Kaspa’s design directly neutralizes the incentives behind selfish mining and offers one of the strongest resistances among Proof-of-Work networks.