oss-sec mailing list archives
Re: CVE Request - multiple ghostscript -dSAFER sandbox problems
From: Tavis Ormandy <taviso () google com>
Date: Wed, 5 Oct 2016 09:54:07 -0700
On Wed, Oct 5, 2016 at 9:47 AM, Hanno Böck <hanno () hboeck de> wrote:
On Wed, 5 Oct 2016 09:13:03 -0700 Tavis Ormandy <taviso () google com> wrote:If you're using ImageMagick, I would recommend disabling the PS, EPS, PDF and XPS coders in policy.xml. Applications like gimp, evince, claws, and most other applications that generate thumbnails of PDF/PS documents should probably not do so without a prompt (NOTE: A lot of packages do thisI was surprised to see evince in this list. It uses poppler for pdf and libspectre for postscript, so there seems to be no use of ghostscript (maybe in an older version). Also for claws the only use of ghostscript is in a plugin that's not enabled by default.
It might be an old version but the version I have on RHEL7 and Ubuntu LTS both invoke gs by default. $ evince --version GNOME Document Viewer 3.14.2
While I agree that avoiding parsing for things like thumbnails should be tried I still wonder what the overall solution to this is. Because even if we avoid non-prompted ps parsing we still want to be able to parse PS files without code execution. Do you feel dSAFER could be secured or is this a loosing battle?
As I understand it, there are also complicated licensing issues with ghostscript that are going to impede progress. The problem is a big mess.
-- Hanno Böck https://hboeck.de/ mail/jabber: hanno () hboeck de GPG: FE73757FA60E4E21B937579FA5880072BBB51E42
Current thread:
- CVE Request - multiple ghostscript -dSAFER sandbox problems Tavis Ormandy (Oct 05)
- Re: CVE Request - multiple ghostscript -dSAFER sandbox problems Hanno Böck (Oct 05)
- Re: CVE Request - multiple ghostscript -dSAFER sandbox problems Tavis Ormandy (Oct 05)
- Re: CVE Request - multiple ghostscript -dSAFER sandbox problems Tavis Ormandy (Oct 05)
- Re: CVE Request - multiple ghostscript -dSAFER sandbox problems Tavis Ormandy (Oct 05)
- Re: CVE Request - multiple ghostscript -dSAFER sandbox problems Hanno Böck (Oct 05)
- Re: CVE Request - multiple ghostscript -dSAFER sandbox problems Tavis Ormandy (Oct 05)
- Re: CVE Request - multiple ghostscript -dSAFER sandbox problems Hanno Böck (Oct 05)
- Re: CVE Request - multiple ghostscript -dSAFER sandbox problems Bob Friesenhahn (Oct 05)
- Re: CVE Request - multiple ghostscript -dSAFER sandbox problems Hanno Böck (Oct 05)
- Re: CVE Request - multiple ghostscript -dSAFER sandbox problems Jakub Wilk (Oct 05)
- Re: CVE Request - multiple ghostscript -dSAFER sandbox problems Florian Weimer (Oct 05)
- Re: Re: CVE Request - multiple ghostscript -dSAFER sandbox problems Cedric Buissart (Oct 19)