Re: radvd 1.8.2 released with security fixes

[Vasiliy Kulikov <segoon () openwall com>]

On Fri, Oct 07, 2011 at 15:41 +0100, John Haxby wrote:
> On 07/10/11 14:03, Robert Święcki wrote:
> > On Fri, Oct 7, 2011 at 12:35 PM, Huzaifa Sidhpurwala
> > <huzaifas () redhat com> wrote:
> > > Shouldnt this be:
> > >
> > >        /* No path traversal */
> > >        if (strstr(iface, "..") || strchr(iface, '/'))
> > >                return -1;
> > FWIW, this will reject too much;
> >
> > /path/to/sth..jpg
>
> Indeed, since I don't believe that iface can reasonably include a "/"
> its sufficient to check for that.   If not then you need to check for
> "../" at the beginning of iface and "/.." anywhere else in it.   But
> simply forbidding "/" should be fine.

Crap, thank you for noticing it, guys.  The fix should be:

https://github.com/reubenhwk/radvd/commit/7a1471b62da88373e8f4209d503307c5d841b81f

Now, "", "..", "." and filenames with "/" inside are denied.


Thanks,

-- 
Vasiliy Kulikov
http://www.openwall.com - bringing security into open computing environments