Skip site navigation (1)Skip section navigation (2)
Date:      Wed, 30 Nov 2022 22:38:55 +0000
From:      Brooks Davis <brooks@freebsd.org>
To:        mike tancsa <mike@sentex.net>
Cc:        Dev Null <devnull@apt322.org>, freebsd-security@freebsd.org
Subject:   Re: FreeBSD Security Advisory FreeBSD-SA-22:15.ping
Message-ID:  <20221130223855.GA89753@spindle.one-eyed-alien.net>
In-Reply-To: <2b590fd0-8b02-1344-d501-005c6cd9fb8f@sentex.net>
References:  <20221130004601.043CE1C623@freefall.freebsd.org> <3dc86282-165d-8562-5cba-0da9896557b9@sentex.net> <e9a7b2ca-a4a4-5b99-f915-0db46b60d1e8@apt322.org> <2b590fd0-8b02-1344-d501-005c6cd9fb8f@sentex.net>

next in thread | previous in thread | raw e-mail | index | archive | help

--pWyiEgJYm5f9v55/
Content-Type: text/plain; charset=us-ascii
Content-Disposition: inline
Content-Transfer-Encoding: quoted-printable

On Wed, Nov 30, 2022 at 05:03:10PM -0500, mike tancsa wrote:
> On 11/30/2022 4:58 PM, Dev Null wrote:
> >
> > Easily to exploit in a test environment, but difficult to be exploited=
=20
> > in the wild, since the flaw only can be exploited in the ICMP reply,=20
> > so the vulnerable machine NEEDS to make an ICMP request first.
> >
> > The attacker in this case, send a short reader in ICMP reply.
> >
> Lets say you know that some device regularly pings, say 8.8.8.8 as part=
=20
> of some connectivity check. If there is no stateful firewall, can the=20
> attacker not just forge the reply on the chance their attack packet=20
> could get there first ??? Or if its the case of "evil ISP" in the middle,=
=20
> it becomes even easier. At that point, how easy is it to actually do=20
> some sort of remote code execution. The SA implies there are mitigating=
=20
> techniques on the OS and in the app.?? I guess its that last part I am=20
> mostly unclear of, how difficult is the RCE if given the first=20
> requirement as a given.

It's probably also worth considering it as a local privilege escalation
attack.  The attacker will need to control a ping server, but it's often
the case that enough ICMP traffic is allowed out for that to work and in
that case they have unlimited tries to defeat any statistical mitigations
(unless the admin spots all the ping crashes).

-- Brooks

--pWyiEgJYm5f9v55/
Content-Type: application/pgp-signature; name="signature.asc"

-----BEGIN PGP SIGNATURE-----

iQEcBAEBAgAGBQJjh9t+AAoJEKzQXbSebgfASvIH/jNVfXbAcuK9GcxBn+EaJIxk
3bVFou5EfndYTtLjl+6zIOAnFs3qFcy1IuQoz7WW14m0a8XhLDUd18eF/spVSTOc
bJ1Rfqc65rwpYD0/f/R3qH4k//eF1lrb0t0JEAbCUwNTZ5ciklhBlANtPYuzCyJy
M6kIl5v8My8IV3ZlioGJs7aNOXI5SJc8cP76DxsqfUzmeP4EFk/Nwaf2wlAEBaH9
YgZocCRoY+xlUOi4SZc3kdPDvUh1F3kGr98tqZJtwLn0uyvmaWmZcsvwwRkel++Z
9PzbgwYKUAl3F7x9iMVef1VOVmGP1PennSNNVSF8Tya31495H8szELrLTgnI8do=
=ewxW
-----END PGP SIGNATURE-----

--pWyiEgJYm5f9v55/--



Want to link to this message? Use this URL: <https://mail-archive.FreeBSD.org/cgi/mid.cgi?20221130223855.GA89753>