From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from sog-mx-2.v43.ch3.sourceforge.com ([172.29.43.192] helo=mx.sourceforge.net) by sfs-ml-2.v29.ch3.sourceforge.com with esmtp (Exim 4.76) (envelope-from ) id 1UMkWs-0005sM-3V for bitcoin-development@lists.sourceforge.net; Mon, 01 Apr 2013 19:36:30 +0000 Received-SPF: pass (sog-mx-2.v43.ch3.sourceforge.com: domain of praus.net designates 209.85.215.42 as permitted sender) client-ip=209.85.215.42; envelope-from=petr@praus.net; helo=mail-la0-f42.google.com; Received: from mail-la0-f42.google.com ([209.85.215.42]) by sog-mx-2.v43.ch3.sourceforge.com with esmtps (TLSv1:RC4-SHA:128) (Exim 4.76) id 1UMkWp-00038t-Jt for bitcoin-development@lists.sourceforge.net; Mon, 01 Apr 2013 19:36:30 +0000 Received: by mail-la0-f42.google.com with SMTP id fe20so2431151lab.29 for ; Mon, 01 Apr 2013 12:36:20 -0700 (PDT) X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=google.com; s=20120113; h=x-received:mime-version:x-originating-ip:in-reply-to:references :from:date:message-id:subject:to:cc:content-type:x-gm-message-state; bh=sR0SBDTZptBiS7LVp2F842T0+wbHvs2+uryHQF4eYbg=; b=g1JqmCZYkemcKVfDwWY+5dnOGsL6gPjQwwDhF2ISJgFYXUeayErNVRvDOrsM0U5VIn fNfsRPtK0QD5ITllSZfnPkx0jJ0dVndOcFXHcn9KSJQE2DfvyhVjHoyDjYDuAF8u484E EegczJCQ4Cx71P0rVjtC6xkpGetcGboNc2rvQxoJUZR7ipK1cwnTtSSFMB824QACvx8v w+xS3QtMX9rjpdRn9lWtTICpbbZCypeLJ0tpWSLVPQ5tHXsnZxGp/oaYlBdcp7xpCdU/ WFPr7lW8T7V6lgB+EltbNPbAUchXIrhSc96Ar3hdaR+5x/0UvbLf5pQzpHL6UhpRzEtK dGkA== X-Received: by 10.112.137.135 with SMTP id qi7mr6173958lbb.117.1364840928259; Mon, 01 Apr 2013 11:28:48 -0700 (PDT) MIME-Version: 1.0 Received: by 10.112.35.107 with HTTP; Mon, 1 Apr 2013 11:28:28 -0700 (PDT) X-Originating-IP: [129.62.151.28] In-Reply-To: References: From: Petr Praus Date: Mon, 1 Apr 2013 13:28:28 -0500 Message-ID: To: Melvin Carvalho Content-Type: multipart/alternative; boundary=089e012292fab445c404d950ca84 X-Gm-Message-State: ALoCoQkfesYoec5eDmoJszr+gKLm1CcSeoesvz7Dx35uLe0cuApOAGpWeVKoGsNsXf8ItdzZTaKw X-Spam-Score: -0.6 (/) X-Spam-Report: Spam Filtering performed by mx.sourceforge.net. See http://spamassassin.org/tag/ for more details. -1.5 SPF_CHECK_PASS SPF reports sender host as permitted sender for sender-domain -0.0 SPF_PASS SPF: sender matches SPF record 1.0 HTML_MESSAGE BODY: HTML included in message -0.1 DKIM_VALID_AU Message has a valid DKIM or DK signature from author's domain 0.1 DKIM_SIGNED Message has a DKIM or DK signature, not necessarily valid -0.1 DKIM_VALID Message has at least one valid DKIM or DK signature X-Headers-End: 1UMkWp-00038t-Jt Cc: Bitcoin Dev Subject: Re: [Bitcoin-development] bitcoin pull requests X-BeenThere: bitcoin-development@lists.sourceforge.net X-Mailman-Version: 2.1.9 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Mon, 01 Apr 2013 19:36:30 -0000 --089e012292fab445c404d950ca84 Content-Type: text/plain; charset=UTF-8 An attacker would have to find a collision between two specific pieces of code - his malicious code and a useful innoculous code that would be accepted as pull request. This is the second, much harder case in the birthday problem. When people talk about SHA-1 being broken they actually mean the first case in the birthday problem - find any two arbitrary values that hash to the same value. So, no I don't think it's a feasible attack vector any time soon. Besides, with that kind of hashing power, it might be more feasible to cause problems in the chain by e.g. constantly splitting it. On 1 April 2013 03:26, Melvin Carvalho wrote: > I was just looking at: > > https://bitcointalk.org/index.php?topic=4571.0 > > I'm just curious if there is a possible attack vector here based on the > fact that git uses the relatively week SHA1 > > Could a seemingly innocuous pull request generate another file with a > backdoor/nonce combination that slips under the radar? > > Apologies if this has come up before ... > > > ------------------------------------------------------------------------------ > Own the Future-Intel® Level Up Game Demo Contest 2013 > Rise to greatness in Intel's independent game demo contest. > Compete for recognition, cash, and the chance to get your game > on Steam. $5K grand prize plus 10 genre and skill prizes. > Submit your demo by 6/6/13. http://p.sf.net/sfu/intel_levelupd2d > _______________________________________________ > Bitcoin-development mailing list > Bitcoin-development@lists.sourceforge.net > https://lists.sourceforge.net/lists/listinfo/bitcoin-development > > --089e012292fab445c404d950ca84 Content-Type: text/html; charset=UTF-8 Content-Transfer-Encoding: quoted-printable
An attacker would have to find a collision between two spe= cific pieces of code - his malicious code and a useful innoculous code that= would be accepted as pull request. This is the second, much harder case in= the birthday problem. When people talk about SHA-1 being broken they actua= lly mean the first case in the birthday problem - find any two arbitrary va= lues that hash to the same value. So, no I don't think it's a feasi= ble attack vector any time soon.

Besides, with that kind of hashing power, it might be = more feasible to cause problems in the chain by e.g. constantly splitting i= t.


On 1 April 2013 03:26, Melvin Carvalho <melvincarvalho@gmail.com> wrote:
I'm just curio= us if there is a possible attack vector here based on the fact that git use= s the relatively week SHA1

Could a seemingly innocuous pull request generate another file wi= th a backdoor/nonce combination that slips under the radar?

Ap= ologies if this has come up before ...

-----------------------------------------------------------------------= -------
Own the Future-Intel&reg; Level Up Game Demo Contest 2013
Rise to greatness in Intel's independent game demo contest.
Compete for recognition, cash, and the chance to get your game
on Steam. $5K grand prize plus 10 genre and skill prizes.
Submit your demo by 6/6/13. http://p.sf.net/sfu/intel_levelupd2d
___________= ____________________________________
Bitcoin-development mailing list
Bitcoin-develo= pment@lists.sourceforge.net
https://lists.sourceforge.net/lists/listinfo/bitcoin-de= velopment


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