The Mempool Anarchist’s Cookbook w/ Portland HODL

Portland HODL explores “poison blocks” – a vulnerability in Bitcoin where malicious miners can craft blocks that take excessive time to validate (25+ minutes on modern hardware, 11+ hours on a Raspberry Pi). The demonstration reveals how quadratic hashing vulnerabilities and signature validation can be exploited to essentially “DOS” Bitcoin nodes, rendering them useless during validation. While difficult to execute without mining power, the attack highlights the need for potential consensus changes like the “great consensus cleanup” to prevent network disruption. An eye-opening look at Bitcoin’s validation challenges. Alt title: “The Mempool Anarchist’s Cookbook”

This presentation was recorded live at OPNEXT, a Bitcoin scaling conference. For more info go to opnext.dev

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# Notes:

– Poison block takes 25 minutes to validate on Xeon

– 11+ hours to validate on a Raspberry Pi

– Attack requires ~150 blocks of setup transactions

– Setup could cost approximately $300,000

– Validation uses ~4 million signature operations

– RPC becomes unresponsive during validation

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