From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from whitealder.osuosl.org (smtp1.osuosl.org [140.211.166.138]) by lists.linuxfoundation.org (Postfix) with ESMTP id 4916DC0171 for ; Fri, 31 Jan 2020 13:38:44 +0000 (UTC) Received: from localhost (localhost [127.0.0.1]) by whitealder.osuosl.org (Postfix) with ESMTP id 35DBB86B3B for ; Fri, 31 Jan 2020 13:38:44 +0000 (UTC) X-Virus-Scanned: amavisd-new at osuosl.org Received: from whitealder.osuosl.org ([127.0.0.1]) by localhost (.osuosl.org [127.0.0.1]) (amavisd-new, port 10024) with ESMTP id 9DXAjJADAvzv for ; Fri, 31 Jan 2020 13:38:43 +0000 (UTC) X-Greylist: domain auto-whitelisted by SQLgrey-1.7.6 Received: from mail-io1-f66.google.com (mail-io1-f66.google.com [209.85.166.66]) by whitealder.osuosl.org (Postfix) with ESMTPS id 62A9A830FD for ; Fri, 31 Jan 2020 13:38:43 +0000 (UTC) Received: by mail-io1-f66.google.com with SMTP id s24so8170018iog.5 for ; Fri, 31 Jan 2020 05:38:43 -0800 (PST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20161025; h=mime-version:from:date:message-id:subject:to; bh=HlYkjFFbCv4FoWCjoi6mbpX2LWOQAHvt1xCQ1QGfnZ4=; b=dlgiukx/4zCpSC2+RwNwzhth2vaXMCJqyWK4tFFmQ1TNT3POYhKR14/Wx3p8Bbhuvs 699w8tLiamiL8KPhVsjQ841Jq62zTcsGj4VTMaM+5V3iw/iH84SfHqhr+ZscPqlhvkH0 nqJBrchOKVCr8APYmIIMjM9IYAMrNtkgyCOYk63dChJjRwmXQ4oDLeNe1iEE8ABd94hO jGFmbV2jGJGdWQ0c5e2L1R2JzYfoHgsbMC9atWqfhMzJoGyc9A9TZ19p0neN5s5uIWHr PpEyTiRfMKZXs54Mds8W5u7i+L4qxdASDuCDb1smSZ52ot5xkS5OtcFOW3/Qjlt9gyUj G6Yw== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:mime-version:from:date:message-id:subject:to; bh=HlYkjFFbCv4FoWCjoi6mbpX2LWOQAHvt1xCQ1QGfnZ4=; b=W/XqsP2MSiaVp6KnkM6B3bTyx6MjRGrklr4fWkyMosg8gQV1evjbJZnzi55xnbMlcv a8+8sl7Z0JIvnsgyf+r6BNB4YbVq3rOFennexaPyePX44vwu3dom93Eh5UtHAQX5mX+w OmpbEEGG8vLzx/VUMBgweZQfB3MWeHbUAIhEGuClgr/XJpjKBb67thVfBSQtS8XQZzMK auK8haFRHVp9uuwleWH2xMOd4fqSsUIcvl5z75ilFc608WzpPRWo+DTzV0gO35CQDsqO ngXTvUW21/QM+/2hh1JGCUrfLflSg0rgd0xo7OB8v2WL59lZbPH5MUyQGlwuhOuoY13X LccA== X-Gm-Message-State: APjAAAU9QuW2P3O13EUEq2V4zVhoE/NzQPvktTTOvmxImUyYTN7Y5b9e aSxANTJVtjTemTQB9n/Em1/y9onVMS8kKoSrCLh0Y/wz/L8= X-Google-Smtp-Source: APXvYqxWtAV2loG4xDvwLf5LzYVSPFPFYtmwEz3VmCv9NdSILIrTV6Gk8vzldOSp0ogozafNHb0OPeWAUpXvR66LEWY= X-Received: by 2002:a6b:92d4:: with SMTP id u203mr8639249iod.288.1580477922475; Fri, 31 Jan 2020 05:38:42 -0800 (PST) MIME-Version: 1.0 From: ha su Date: Fri, 31 Jan 2020 14:38:22 +0100 Message-ID: To: bitcoin-dev@lists.linuxfoundation.org Content-Type: multipart/alternative; boundary="0000000000002504f0059d6fb12d" X-Mailman-Approved-At: Sat, 01 Feb 2020 22:12:53 +0000 Subject: [bitcoin-dev] Purge attacks (spin on sabotage attacks) X-BeenThere: bitcoin-dev@lists.linuxfoundation.org X-Mailman-Version: 2.1.15 Precedence: list List-Id: Bitcoin Protocol Discussion List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Fri, 31 Jan 2020 13:38:44 -0000 --0000000000002504f0059d6fb12d Content-Type: text/plain; charset="UTF-8" Content-Transfer-Encoding: quoted-printable Hi all, I think I discovered an interesting form of sabotage attack (possible for miners) that tries to create coordination disincentives among Bitcoin users - named after the dystopian movie The Purge, where all crime is legal for one night every year. TLDR * An attacker replaces the most recent blocks full of transactions with empty blocks. * Previously confirmed txns return into the mempool, where anyone with a minimum of technical knowledge or access to public tools can opportunistically double-spend their txns back to themselves. (the process is the same as double-spending regular zero-conf txns) The attack seems useful to undermine trust in Bitcoin's assurances, e.g. the future finality of transactions. It differs from other forms of sabotage (e.g. DoS by mining only empty blocks) in that it specifically disrupts the coordination process among users in response to the attack. By giving some users a chance to benefit from the attack, the attacker gives them a vested interest in staying on the attack chain. If enough users accept the invitation to double-spend, it might become harder to come to consensus on how to deal with the attack. Purge attacks probably don=E2=80=99t constitute a bigger risk than other kn= own forms of sabotage attacks, but seem like an interesting spin where the attacker specifically targets the pre-coordination of defenders. You can find the full report, incl. some mitigations against sabotage attacks, at https://blog.deribit.com/insights/destabilizing-bitcoin-consensus-with-purg= e-attacks/ Your feedback is highly appreciated. Regards, Hasu --0000000000002504f0059d6fb12d Content-Type: text/html; charset="UTF-8" Content-Transfer-Encoding: quoted-printable
Hi all,

I think I discovered an interesting form of= sabotage attack (possible for miners) that tries to create coordination di= sincentives among Bitcoin users - named after the dystopian movie The Purge= , where all crime is legal for one night every year.

TLDR
* An at= tacker replaces the most recent blocks full of transactions with empty bloc= ks.
* Previously confirmed txns return into the mempool, where anyone w= ith a minimum of technical knowledge or access to public tools can opportun= istically double-spend their txns back to themselves. (the process is the s= ame as double-spending regular zero-conf txns)

The attack seems usef= ul to undermine trust in Bitcoin's assurances, e.g. the future finality= of transactions. It differs from other forms of sabotage (e.g. DoS by mini= ng only empty blocks) in that it specifically disrupts the coordination=C2= =A0process among users in response to the attack.=C2=A0

By giving so= me users a chance to benefit from the attack, the attacker gives them a ves= ted interest in staying on the attack chain. If enough users accept the inv= itation to double-spend, it might become harder to come to consensus on how= to deal with the attack.

Purge attacks probably don=E2=80=99t const= itute a bigger risk than other known forms of sabotage attacks, but seem li= ke an interesting spin where the attacker specifically targets the pre-coor= dination of defenders.

You can find the full report, incl. some miti= gations against sabotage attacks, at=C2=A0https://bl= og.deribit.com/insights/destabilizing-bitcoin-consensus-with-purge-attacks/=

Your feedback is highly appreciated.

Regards,
Hasu
--0000000000002504f0059d6fb12d--