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On Sun, Sep 14, 2014 at 10:38:41PM +0000, hasufell wrote: |
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> Yes, there is a possible attack vector mentioned in this comment |
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> https://bugs.gentoo.org/show_bug.cgi?id=502060#c16 |
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From that comment, the point 1.2 is highly unlikely [1]: |
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1. Attacker constructs a init.d script, regular part at the start, |
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malicious part at the end |
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1.1. This would be fairly simple, just construct two start() |
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functions, one of which is mundane, the other is malicious. |
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1.2. Both variants of the script have the same SHA1... |
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> So we'd basically end up using either "git cherry-pick" or "git am" |
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> for "pulling" user stuff, so that we also sign the blobs. |
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Rebasing the original commits doesn't protect you from the birthday |
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attach either, because the vulnerable hash is likely going to still be |
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in the rebased commit's tree. All rebasing does is swap the committer |
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and drop the initial signature. |
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Cheers, |
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Trevor |
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[1]: http://article.gmane.org/gmane.comp.version-control.git/210622 |
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-- |
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