Openwall GNU/*/Linux - a small security-enhanced Linux distro for servers
[<prev] [next>] [<thread-prev] [thread-next>] [day] [month] [year] [list]
Date: Tue, 22 Jan 2013 08:47:46 -0700
From: Vincent Danen <vdanen@...hat.com>
To: Sebastian Krahmer <krahmer@...e.de>
Cc: oss-security@...ts.openwall.com
Subject: Re: CVE Request coreutils

* [2013-01-22 08:25:23 +0100] Sebastian Krahmer wrote:

>Generally, I see your point. However sometimes services running as
>root 'sort' or 'uniq' user input e.g. via grepping logfiles etc,
>so there is indeed a real chance to indirectly trigger a privilege
>escalation. The past shows that segfaults can be turned into a
>code exec often. Its a stack overflow after all.

Do you believe this would be the case with modern GCC/Glibc hardening
though?  Wouldn't this just be rendered a crash?

But even then, if we're talking about logfiles (which is a reasonable
case) you'd have to be allowing user-controlled input to your logs,
which would mean you'd have another problem.

I'm also assuming, based on the comments in the first bug, that you need
a really large line (not just an entire file, but one line).  How likely
is it that you would be grepping a log file with ~10MB of data on one
line?

Perhaps root grepping/sorting/etc. a logfile is a valid use-case and
some user-supplied input could be stored in there (perhaps a crafted
apache url, etc. or maybe a local user running logger to inject a custom
log entry), but do these programs even allow for a ~10MB in length URL
or data?

(I've not looked, maybe they do?)

>On Mon, Jan 21, 2013 at 06:33:07PM -0700, Kurt Seifried wrote:
>> -----BEGIN PGP SIGNED MESSAGE-----
>> Hash: SHA1
>>
>> On 01/21/2013 01:39 PM, Vincent Danen wrote:
>> > * [2013-01-21 19:17:49 +0100] Moritz Muehlenhoff wrote:
>> >
>> >>> Can someone assign a CVE id for a buffer overflow in
>> >>> coreutils? Its the same code snippet (coreutils-i18n.patch) and
>> >>> it affects sort, uniq and join:
>> >>>
>> >>> https://bugzilla.novell.com/show_bug.cgi?id=798538
>> >>> https://bugzilla.novell.com/show_bug.cgi?id=796243
>> >>> https://bugzilla.novell.com/show_bug.cgi?id=798541
>> >>
>> >> Could you send the faulty patch to the list so that distros can
>> >> validate that they don't include it themselves?
>> >
>> > Red Hat/Fedora do include this patch, so it's more than just SUSE
>> > that ships them.  However, when I was looking at them last week,
>> > this struck me as just a non-exploitable crash and unless I'm
>> > missing something, I think it would be quite the stretch to call it
>> > a security flaw.
>>
>> Agreed, there is no significant impact of exploitation and there is no
>> real easy way to trick a victim into doing this (and even if you do,
>> so what? now if it was code exec we might be talking about something
>> interesting).
>>
>> - --
>> Kurt Seifried Red Hat Security Response Team (SRT)
>> PGP: 0x5E267993 A90B F995 7350 148F 66BF 7554 160D 4553 5E26 7993
>>
>> -----BEGIN PGP SIGNATURE-----
>> Version: GnuPG v1.4.12 (GNU/Linux)
>>
>> iQIcBAEBAgAGBQJQ/exTAAoJEBYNRVNeJnmTrW0P/3B/L/SE7akzCPUU6TW9wy1L
>> Rpb8IIITLCz1qkb/gkUayUFJHQDjpEfmxNPJQWm1fJBrWI0bFr0wvHRuGHgyXZEA
>> Bl+js2w0uu7kAEEf1bHjZjf7zVHZ2tvoAdzi8ypLASZisxXwSa4acy++sqmPTrSf
>> oNOu3ChqG919VSLfD8Zf5AsGFs6G3tRzNEmYtvllt9liUFKgL6WsCNWNWUZdpWm2
>> crZPdyf343VvQcG5p7vYPEJLUBmnUSIauakssYPxGSp1vNBDNCC8xuVnyf1KOLfc
>> r3BHDPRX5ooe8EcoK/zgo1owK7tP9d7FT94gIsJte3OUOP5dq6LR/R0ZMMUsneNA
>> EjJScDCkh0hcZYCdJkqtah5aoAYI6IQvXJVtbwDM+rAvHfoMV2nkbWVZL0SgCMW/
>> B/hvhQJejFN3dd0wfiO5sQf5o2UxxYyIIpTE+GQP/pe8Q7F1BzR5nV87Jd3sWQY8
>> J873KRADBgt4RwbVUpI7dUL67UeRZCN4FiNtYYEuD5BeJWMSVoVXRHP7zBkx8GhG
>> vgfUc02+IyxS0HTO5HIxSJnLYOSa++SxJ4/w85aqcWPLrLHhL4s1k4GELPg/JhdW
>> Um35zAkcLNnxsxySCMIWZKEUTZ3xdpBspc3QVkw/IoyZpk+QhQTM2S/C3yWv4Q0z
>> xwHEEqesvl8l7UlpQ2mC
>> =rw4/
>> -----END PGP SIGNATURE-----
>
>-- 
>
>~ perl self.pl
>~ $_='print"\$_=\47$_\47;eval"';eval
>~ krahmer@...e.de - SuSE Security Team
>

-- 
Vincent Danen / Red Hat Security Response Team 

Powered by blists - more mailing lists

Your e-mail address:

Please check out the Open Source Software Security Wiki, which is counterpart to this mailing list.

Confused about mailing lists and their use? Read about mailing lists on Wikipedia and check out these guidelines on proper formatting of your messages.