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From: Melvin Carvalho <melvincarvalho@gmail.com>
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Cc: Bitcoin Dev <bitcoin-development@lists.sourceforge.net>
Subject: Re: [Bitcoin-development] bitcoin pull requests
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On 1 April 2013 20:28, Petr Praus <petr@praus.net> wrote:
> 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.
>
OK, maybe im being *way* too paranoid here ... but what if someone had
access to github, could they replace one file with one they had prepared at
some point?
>
>
> On 1 April 2013 03:26, Melvin Carvalho <melvincarvalho@gmail.com> 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
>>
>>
>
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Content-Type: text/html; charset=ISO-8859-1
Content-Transfer-Encoding: quoted-printable
<div dir=3D"ltr"><br><div class=3D"gmail_extra"><br><br><div class=3D"gmail=
_quote">On 1 April 2013 20:28, Petr Praus <span dir=3D"ltr"><<a href=3D"=
mailto:petr@praus.net" target=3D"_blank">petr@praus.net</a>></span> wrot=
e:<br><blockquote class=3D"gmail_quote" style=3D"margin:0 0 0 .8ex;border-l=
eft:1px #ccc solid;padding-left:1ex">
<div dir=3D"ltr">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.<div>
<br></div><div>Besides, with that kind of hashing power, it might be more f=
easible to cause problems in the chain by e.g. constantly splitting it.</di=
v></div></blockquote><div><br></div><div>OK, maybe im being *way* too paran=
oid here ... but what if someone had access to github, could they replace o=
ne file with one they had prepared at some point?<br>
</div><div>=A0</div><blockquote class=3D"gmail_quote" style=3D"margin:0 0 0=
.8ex;border-left:1px #ccc solid;padding-left:1ex"><div class=3D"gmail_extr=
a"><br><br><div class=3D"gmail_quote"><div><div class=3D"h5">
On 1 April 2013 03:26, Melvin Carvalho <span dir=3D"ltr"><<a href=3D"mai=
lto:melvincarvalho@gmail.com" target=3D"_blank">melvincarvalho@gmail.com</a=
>></span> wrote:<br></div></div><blockquote class=3D"gmail_quote" style=
=3D"margin:0 0 0 .8ex;border-left:1px #ccc solid;padding-left:1ex">
<div><div class=3D"h5">
<div dir=3D"ltr"><div><div><div>I was just looking at:<br><br><a href=3D"ht=
tps://bitcointalk.org/index.php?topic=3D4571.0" target=3D"_blank">https://b=
itcointalk.org/index.php?topic=3D4571.0</a><br><br></div>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<br>
<br></div>Could a seemingly innocuous pull request generate another file wi=
th a backdoor/nonce combination that slips under the radar?<br><br></div>Ap=
ologies if this has come up before ...<br></div>
<br></div></div>-----------------------------------------------------------=
-------------------<br>
Own the Future-Intel&reg; Level Up Game Demo Contest 2013<br>
Rise to greatness in Intel's independent game demo contest.<br>
Compete for recognition, cash, and the chance to get your game<br>
on Steam. $5K grand prize plus 10 genre and skill prizes.<br>
Submit your demo by 6/6/13. <a href=3D"http://p.sf.net/sfu/intel_levelupd2d=
" target=3D"_blank">http://p.sf.net/sfu/intel_levelupd2d</a><br>___________=
____________________________________<br>
Bitcoin-development mailing list<br>
<a href=3D"mailto:Bitcoin-development@lists.sourceforge.net" target=3D"_bla=
nk">Bitcoin-development@lists.sourceforge.net</a><br>
<a href=3D"https://lists.sourceforge.net/lists/listinfo/bitcoin-development=
" target=3D"_blank">https://lists.sourceforge.net/lists/listinfo/bitcoin-de=
velopment</a><br>
<br></blockquote></div><br></div>
</blockquote></div><br></div></div>
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