Re: [gentoo-dev] Current unavoidable use of xz utils in Gentoo

[orbea <orbea@riseup.net>]

On Mon, 1 Apr 2024 11:14:15 -0400
Kenton Groombridge <concord@gentoo.org> wrote:

> On 24/03/31 12:13PM, Eddie Chapman wrote:
> > Eli Schwartz wrote:  
> > > On 3/29/24 11:07 PM, Eddie Chapman wrote:
> > >  
> > >> Given what we've learnt in the last 24hrs about xz utilities,
> > >> you could forgive a paranoid person for seriously considering
> > >> getting rid entirely of them from their systems, especially
> > >> since there are suitable alternatives available.  Some might say
> > >> that's a bit extreme, xz-utils will get a thorough audit and it
> > >> will all be fine. But when a malicious actor has been a key
> > >> maintainer of something as complex as a decompression utility
> > >> for years, I'm not sure I could ever trust that codebase again.
> > >> Maybe a complete rewrite will emerge, but I'm personally
> > >> unwilling to continue using xz utils in the meantime for
> > >> uncompressing anything on my systems, even if it is done by an
> > >> unprivileged process.  
> > >
> > >
> > > It suffices to downgrade to the version of xz before a social
> > > engineering attack by a malicious actor to gain maintainership of
> > > the xz project.
> > >
> > > Have you been linked to this yet?
> > > https://www.mail-archive.com/xz-devel@tukaani.org/msg00571.html
> > >
> > > --
> > > Eli Schwartz
> > >  
> > 
> > Yes I saw that yesterday. It only increased my level of concern
> > about the project ten-fold rather than decreased it, particularly
> > because of "he has been helping a lot off-list and is practically a
> > co-maintainer already".
> > 
> >   
> 
> I think it's important to realize that this could have potentially
> happened to any number of various open source projects, not just
> xz-utils. Simply ripping it out and replacing it is not enough to
> prevent these kinds of issues from happening in the future.
> 
> There is a major shifting of perspectives as a result of this
> unfortunate compromise. Right now there are serious considerations
> about banning (or otherwise auditing) binary blobs in some projects.
> There are talks about banning the use of older build systems like
> autotools in favor of ones more easily readable and auditable.

Talk about throwing the baby out with the bathwater...

Its fully possible to write autotools build systems which are simple
and easy to audit. Depending on what blob does it may be far from
trivial or advisable to get rid of it.

This attack as already has been clearly stated is social, not
technical. If xz-utils used meson or cmake instead it would of not
changed the situation.

> Ultimately what is happening is a reflection on how we audit critical
> system components and contributions made to them. Change is not going
> to happen over night.
> 
> We saw a similar shift with OpenSSL's heartbleed, which ultimately led
> to positive changes in code quality and improving their vulnerability
> reporting process.
> 
> There is some good to come of this event, but it's important to
> recognize what went wrong and how open source can improve as a whole.
>