From mboxrd@z Thu Jan  1 00:00:00 1970
From: Ludovic =?UTF-8?Q?Court=C3=A8s?= <ludo@gnu.org>
Subject: bug#37744: Per-user profile directory hijack (CVE-2019-17365 for Nix)
Date: Mon, 14 Oct 2019 09:58:47 +0200
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Cc: GNU Guix maintainers <guix-maintainers@gnu.org>, guix-security@gnu.org

Ludovic Court=C3=A8s <ludo@gnu.org> skribis:

> Looks like we=E2=80=99ll need to do something similar to:
> <https://github.com/NixOS/nix/pull/3136/commits/5a303093dcae1e5ce9212616e=
f18f2ca51020b0d>.

Compared to the Nix build daemon, our daemon can accept connections over
TCP in addition to Unix-domain sockets, so the bit that does:

  store->createUser(userName, userId);

won=E2=80=99t work in that context (it would create =E2=80=98per-user/root=
=E2=80=99.)

I don=E2=80=99t see how to let the daemon create =E2=80=98per-user/$USER=E2=
=80=99 on behalf of
the client for clients connecting over TCP.  Or we=E2=80=99d need to add a
challenge mechanism or authentication.

Thoughts?

Ludo=E2=80=99.