Git 3.0's upcoming SHA-256 default will be a costly mistake
A GitButler post argues Git 3.0's SHA-1 to SHA-256 default will be costly with little security gain.
A GitButler post argues that Git 3.0's plan to change the default object hash from SHA-1 to SHA-256 will impose a costly global migration for little practical security gain. Git has used SHA-1 since 2005, and the author says accidental collisions have not occurred across Git history. Published work including SHAttered in 2017 and SHA-1 is a Shambles in 2020 shows purposeful collisions are theoretically possible, at a cost the post puts in the tens of thousands of dollars. The author says second-preimage replacement of an existing object remains effectively impossible, even for MD5.
- Git 3.0 plans to change the default hash from SHA-1 to SHA-256.
- Published SHA-1 collision attacks exist, but accidental Git collisions are unreported.
- The post says second-preimage attacks remain impractical even for MD5.
- Author argues migration cost outweighs the limited integrity benefit.
Indicators of compromise
auto-extracted · verify before use · export allAll| Type | Indicator | Context |
|---|---|---|
| sha256 | 11043f6a3be7d21e999dc84550886306bee65f4faf4fc9226979108fd1a0b1af | insertion(+) create mode 100644 README.md ❯ git log commit 11043f6a3be7d21e999dc84550886306bee65f4faf4fc9226979108fd1a0b1af (HEAD -> main) Author: Scott Chacon <schacon@gmail.com> Dat |
From the original article
15 min read at blog.gitbutler.com
I've been sitting on this for a few years, mostly because there are smarter people who have been concentrating on this and I don't love being a back seat driver. However, I think that the Git 3. 0 release is about to cost everyone a lot of time and angst for little benefit, and virtually nobody knows what's coming.
By chmaynard · blog.gitbutler.com
A short excerpt; the article and its images belong to the publisher. Summary, key facts and assessment above are AI-written from the article and can be wrong.