{"type":"rich","version":"1.0","author_name":"npub1m230cem2yh3mtdzkg32qhj73uytgkyg5ylxsu083n3tpjnajxx4qqa2np2","author_url":"https://nostr.ae/npub1m230cem2yh3mtdzkg32qhj73uytgkyg5ylxsu083n3tpjnajxx4qqa2np2","provider_name":"njump","provider_url":"https://nostr.ae","html":"📅 Original date posted:2017-02-23\n📝 Original message:On Thu, Feb 23, 2017 at 01:14:09PM -0500, Peter Todd via bitcoin-dev wrote:\n\u003e Worth noting: the impact of the SHA1 collison attack on Git is *not* limited\n\u003e only to maintainers making maliciously colliding Git commits, but also\n\u003e third-party's submitting pull-reqs containing commits, trees, and especially\n\u003e files for which collisions have been found. This is likely to be exploitable in\n\u003e practice with binary files, as reviewers aren't going to necessarily notice\n\u003e garbage at the end of a file needed for the attack; if the attack can be\n\u003e extended to constricted character sets like unicode or ASCII, we're in trouble\n\u003e in general.\n\u003e \n\u003e Concretely, I could prepare a pair of files with the same SHA1 hash, taking\n\u003e into account the header that Git prepends when hashing files. I'd then submit\n\u003e that pull-req to a project with the \"clean\" version of that file. Once the\n\u003e maintainer merges my pull-req, possibly PGP signing the git commit, I then take\n\u003e that signature and distribute the same repo, but with the \"clean\" version\n\u003e replaced by the malicious version of the file.\n\nThinking about this a bit more, the most concerning avenue of attack is likely\nto be tree objects, as I'll bet you you can construct tree objs with garbage at\nthe end that many review tools don't pick up on. :(\n\n-- \nhttps://petertodd.org 'peter'[:-1]@petertodd.org\n-------------- next part --------------\nA non-text attachment was scrubbed...\nName: signature.asc\nType: application/pgp-signature\nSize: 455 bytes\nDesc: Digital signature\nURL: \u003chttp://lists.linuxfoundation.org/pipermail/bitcoin-dev/attachments/20170223/29fe50b5/attachment-0001.sig\u003e"}