From: Leo Famulari <leo@famulari.name>
To: "Ludovic Courtès" <ludo@gnu.org>
Cc: 47229@debbugs.gnu.org
Subject: bug#47229: Local privilege escalation via guix-daemon and ‘--keep-failed’
Date: Sat, 10 Apr 2021 13:56:27 -0400 [thread overview]
Message-ID: <YHHmy4+z9UOunSyB@jasmine.lan> (raw)
In-Reply-To: <87lfaksock.fsf@gnu.org>
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On Thu, Mar 18, 2021 at 12:17:15PM +0100, Ludovic Courtès wrote:
> Vulnerability
> ~~~~~~~~~~~~~
>
> The attack consists in having an unprivileged user spawn a build
> process, for instance with ‘guix build’, that makes its build directory
> world-writable. The user then creates a hardlink within the build
> directory to a root-owned file from outside of the build directory, such
> as ‘/etc/shadow’. If the user passed the ‘--keep-failed’ option and the
> build eventually fails, the daemon changes ownership of the whole build
> tree, including the hardlink, to the user. At that point, the user has
> write access to the target file.
This has been assigned CVE-2021-27851.
Soon, it should be available in the CVE database at
<https://cve.mitre.org/cgi-bin/cvename.cgi?name=CVE-2021-27851>
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prev parent reply other threads:[~2021-04-10 17:57 UTC|newest]
Thread overview: 6+ messages / expand[flat|nested] mbox.gz Atom feed top
2021-03-18 11:17 bug#47229: Local privilege escalation via guix-daemon and ‘--keep-failed’ Ludovic Courtès
2021-03-18 11:45 ` Ludovic Courtès
2021-03-18 13:14 ` Ludovic Courtès
2021-03-18 11:53 ` Léo Le Bouter via Bug reports for GNU Guix
2021-03-18 21:10 ` Leo Famulari
2021-04-10 17:56 ` Leo Famulari [this message]
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