Re: Git ransom campaign incident report - May 2019
- Date: Mon, 20 May 2019 16:43:31 +0200 (CEST)
- From: Johannes Schindelin <Johannes.Schindelin@xxxxxx>
- Subject: Re: Git ransom campaign incident report - May 2019
On Sun, 19 May 2019, Jeff King wrote:
> On Fri, May 17, 2019 at 06:20:31PM -0400, Jeff King wrote:
> > What if we did this:
> > 1. Do not ever write the password part of a URL into config.
> > 2. When we extract the user/pass out of a URL, put them into the
> > credential struct, so that when we successfully authenticate, we
> > trigger storage. This _might_ actually happen already, but we
> > should definitely confirm it.
> > 3. If the user has no credential helper defined, then do one of:
> > a. Warn them that the credential was not recorded, but that they
> > can use "git clone -c credential.helper=store" as a fallback
> > (but probably worded in a way to recommend using something
> > stronger if possible).
> > This is slightly annoying because following the advice requires
> > re-cloning. Fixing it up from there is more like:
> > git config credential.helper store
> > git fetch
> > [interactively input password]
> > b. Just use credential-store. Optionally notify them of what
> > happened (and that they might want to choose a better helper).
> So here are patches to do that. Step 2 is indeed how things work
> already, so nothing was needed there (there are still 3 patches because
> there was a bit of prep-work ;) ).
Thank you for working on this!!!
> I did 3b here: automagically enabling credential-store. I'm still on the
> fence on whether that's a good idea or not.
I think you're right, it is a good idea. It is built by default (because
it has no 3rd-party dependencies), and it should be "safe enough".
I'll just have to look into mapping the Unix-y `chmod()` to a
Windows-appropriate ACL action, I guess. AFAICT we don't do that yet.
> I don't have any data on how many victims of this ransom campaign might
> have been helped by this. But it certainly seems like a decent best
> practice. I'd hope that _most_ people have moved on to using a
> credential helper and supplying the initial password interactively these
> days; this is really just aimed at people who don't know better. So the
> goal is making them a bit more secure, but also educating them about the
> other options. Hopefully without breaking any workflows. :)
Well, let's also not underestimate the side effect of educating people
(even transitively) by the mere action of doing something about it and
talking about that.
> [1/3]: transport_anonymize_url(): support retaining username
> [2/3]: clone: avoid storing URL passwords in config
> [3/3]: clone: auto-enable git-credential-store when necessary
> builtin/clone.c | 37 +++++++++++++++++++++++++++++++++++--
> credential.c | 13 +++++++++++++
> credential.h | 6 ++++++
> t/t5550-http-fetch-dumb.sh | 12 ++++++++++++
> transport.c | 21 ++++++++++++++-------
> transport.h | 11 ++++++++++-
> 6 files changed, 90 insertions(+), 10 deletions(-)