Feedback-ID: i525146e8:Fastmail
Date: Sat, 21 Oct 2023 00:15:21 +0000
From: Peter Todd <pete@petertodd.org>
To: Matt Corallo <lf-lists@mattcorallo.com>
Message-ID: <ZTMYGcRvHh0Iwe2y@petertodd.org>
References: <CALZpt+GdyfDotdhrrVkjTALg5DbxJyiS8ruO2S7Ggmi9Ra5B9g@mail.gmail.com>
 <eW4O0HQJ2cbrzZhXSlgeDRWuhgRHXcAxIQCHJiqPh1zUxr270xPvl_tb7C4DUauZy56HaCq6BqGN9p4k-bkqQmLb4EHzPgIxZIZGVPlqyF0=@protonmail.com>
 <64VpLnXQLbeoc895Z9aR7C1CfH6IFxPFDrk0om-md1eqvdMczLSnhwH29T6EWCXgiGQiRqQnAYsezbvNvoPCdcfvCvp__Y8BA1ow5UwY2yQ=@protonmail.com>
 <ZTJW59wQ/4WLZt2h@petertodd.org> <ZTJej/ipIl5hZIUn@petertodd.org>
 <CAGyamEVGe+z96Rc52V0j=a+He3frzhHEk_NPunXA-g1MwXXdGw@mail.gmail.com>
 <1a84a36c-ec23-43b5-9a61-1aafdc188892@mattcorallo.com>
MIME-Version: 1.0
Content-Type: multipart/signed; micalg=pgp-sha512;
 protocol="application/pgp-signature"; boundary="V+kpSR+Yz65nXk9o"
Content-Disposition: inline
In-Reply-To: <1a84a36c-ec23-43b5-9a61-1aafdc188892@mattcorallo.com>
Cc: Bitcoin Protocol Discussion <bitcoin-dev@lists.linuxfoundation.org>,
 security@ariard.me,
 "lightning-dev\\\\\\\\\\\\\\\\@lists.linuxfoundation.org"
 <lightning-dev@lists.linuxfoundation.org>
Subject: Re: [bitcoin-dev] [Lightning-dev] Full Disclosure: CVE-2023-40231 /
 CVE-2023-40232 / CVE-2023-40233 / CVE-2023-40234 "All your mempool are
 belong to us"
Precedence: list


--V+kpSR+Yz65nXk9o
Content-Type: text/plain; charset=us-ascii
Content-Disposition: inline
Content-Transfer-Encoding: quoted-printable

On Fri, Oct 20, 2023 at 05:05:48PM -0400, Matt Corallo wrote:
> Sadly this only is really viable for pre-anchor channels. With anchor
> channels the attack can be performed by either side of the closure, as the
> HTLCs are now, at max, only signed SIGHASH_SINGLE|ANYONECANPAY, allowing =
you
> to add more inputs and perform this attack even as the broadcaster.
>=20
> I don't think its really viable to walk that change back to fix this, as =
it
> also fixed plenty of other issues with channel usability and important
> edge-cases.

What are anchor outputs used for other than increasing fees?

Because if we've pre-signed the full fee range, there is simply no need for
anchor outputs. Under any circumstance we can broadcast a transaction with a
sufficiently high fee to get mined.

--=20
https://petertodd.org 'peter'[:-1]@petertodd.org

--V+kpSR+Yz65nXk9o
Content-Type: application/pgp-signature; name="signature.asc"

-----BEGIN PGP SIGNATURE-----
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=r1Ih
-----END PGP SIGNATURE-----

--V+kpSR+Yz65nXk9o--