Follow @Openwall on Twitter for new release announcements and other news
[<prev] [next>] [<thread-prev] [thread-next>] [day] [month] [year] [list]
Message-ID: <CACC5Q1dPzS3C_9L_vVx4scx7UaE38OqXcC0g6zFPE-Eb-tYRSw@mail.gmail.com>
Date: Mon, 26 Oct 2015 15:21:23 -0500
From: Austin English <austinenglish@...il.com>
To: cve-assign@...re.org, Austin English <austinenglish@...il.com>, 
	oss-security@...ts.openwall.com
Subject: Re: Re: CVE request for wget

On Thu, Oct 1, 2015 at 6:10 PM, Seth Arnold <seth.arnold@...onical.com> wrote:
> On Thu, Oct 01, 2015 at 06:57:26PM -0400, cve-assign@...re.org wrote:
>> If there is any additional Tails vulnerability related to this,
>> another CVE ID may be needed. For example,
>>
>>   https://lists.gnu.org/archive/html/bug-wget/2015-08/msg00050.html
>>
>> says
>>
>>   to be 100% sure, you should add --passive-ftp to your command line.
>>   If you don't do that, your /etc/wgetrc or ~/.wgetrc could include
>>   --no-passive-ftp (or passiveftp = off).
>>
>> If Tails is supposed to try to ensure that, perhaps there's a
>> requirement to have something like:
>>
>>   alias wget="wget --passive-ftp"
>>
>> in a system-wide location (possibly /etc/bash.bashrc). The concept of
>> CVE IDs for "failure of a torify step" issues is new, and we aren't
>> sure of the best approach.
>
> I suspect using a bash alias in a site-wide config might then qualify for
> another CVE in the future, along the lines of "programs that spawn wget
> via system(3), popen(3), or exec family of functions can use unsafe active
> mode by accident". If Tails is in the business of fixing these things
> for safety, removing active ftp support from tools seems like better fix.
>
> Thanks

A fix has been applied to Tails git:
https://labs.riseup.net/code/projects/tails/repository/revisions/b9fd6312435d55dd0bc0b6abdb7994da4d66e2b2

In short, the wget binary is moved to /usr/lib/wget/wget, and a
wrapper script is put in place in /usr/bin/wget. The wrapper ensures
that wget is called via torsocks, and additionally, also forces
--passive-ftp.

Moving wget to /usr/lib/wget/wget gets the potentially dangerous wget
binary out of $PATH. A dedicated attacker could check if /usr/bin/wget
is a script and then parse it to find the actual binary, but that
would need to be a very dedicated attacker and at that point, there
are more feasible attacks available.

-- 
-Austin

Powered by blists - more mailing lists

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.