Re: Re: CVE Request (minor) -- osc: Improper sanitization of terminal emulator escape sequences when displaying build log and build status

[Kurt Seifried <kseifried () redhat com>]

On 02/28/2012 03:44 PM, Marcus Meissner wrote:
> On Tue, Feb 28, 2012 at 06:56:52PM +0100, Jan Lieskovsky wrote:
> > Hello Kurt, Steve, Marcus, vendors,
> >
> >   a security flaw was found in the way osc, the Python language based 
> >   command
> > line client for the openSUSE build service, displayed build logs and build
> > status for particular build. A rogue repository server could use this flaw 
> > to
> > modify window's title, or possibly execute arbitrary commands or overwrite
> > files via a specially-crafted build log or build status output containing an
> > escape sequence for a terminal emulator.
> >
> > References:
> > [1] https://bugzilla.novell.com/show_bug.cgi?id=749335
> > [2] https://bugzilla.redhat.com/show_bug.cgi?id=798353
> >
> > I need to conclude, I don't know how OBS repositories work (if there is a 
> > chance
> > of a rogue server being present). In any case, this issue is on the border
> > (pretty unlikely someone could alter content of OBS package during build --
> > in that case there would be more urgent issues than just particular terminal
> > window title change).
> >
> > But strictly taken, the trust boundary is crossed in the moment, someone
> > would schedule OBS build and wouldn't expect the build log / status can
> > perform terminal "side" effect yet.
> >
> > Marcus, please correct me if you don't agree this should get a CVE 
> > identifier.
> >
> > If no one having objections and request appropriate, could you allocate one?
>
> I am not fully convinced it needs a CVE.
>
> It basically boils down to the old "logfile with content that might be controlled
> by an attacker pasted raw to a terminal" issue.
>
> There is some more control on the person who builds a specific package what is output
> thant there usually is in logfiles though.
>
> A rogue server is unlikely, however a malicious packager could echo "bad escape code"
> in his build and then ask for help on our IRC channels or mailinglists with package Y on project X.
> (anyone can create an account and build packages ... and asking for help is not uncommon)
> e.g. with "look at logfile with: 'osc buildlog home:user foopackage standard i586'.)
>
> Ciao, Marcus

Please use CVE-2012-1095 for this issue.

-- 
Kurt Seifried Red Hat Security Response Team (SRT)