Re: Re: CVE requests: DoS in librsvg parsing SVGs with circular definitions

[Gustavo Grieco <gustavo.grieco () gmail com>]

2016-05-11 0:36 GMT+02:00 Brian May <brian () linuxpenguins xyz>:
> Just did a git bisect against the source. Assuming I got this right, the
> following commits fixed the issue.

Thanks for taking the time to do the git bisect!

> > > They affect the following functions:
> >
> > > * rsvg_cairo_pop_discrete_layer - rsvg_cairo_pop_render_stack -
> > > rsvg_cairo_generate_mask: reproducible using circular-1.svg
> >
> > Use CVE-2016-4347.
>
> Fixed in:
>
> commit a51919f7e1ca9c535390a746fbf6e28c8402dc61
> Author: Benjamin Otte <otte () redhat com>
> Date:   Wed Oct 7 08:45:37 2015 +0200
>
>     rsvg: Add rsvg_acquire_node()
>
>     This function does proper recursion checks when looking up resources
>     from URLs and thereby helps avoiding infinite loops when cyclic
>     references span multiple types of elements.


I think CVE-2016-4347 and CVE-2015-7558 (stack exhaustion due to
cyclic dependency, reported here:
http://www.openwall.com/lists/oss-security/2015/12/21/5) are in fact,
the same issue. This is probably my fault (sorry!).

MITRE: We should reject the the newly assigned one?

Regards,
Gustavo.