[Openswan dev] Re: openswan potential DoS in sarge

Martin Schulze joey at infodrom.org
Wed Apr 26 12:54:24 CEST 2006

Paul Wouters wrote:
> On Sun, 16 Apr 2006, Rene Mayrhofer wrote:
> > [Since I'm CC'ing the list, this is about the pluto crash fixed with 2.4.0,
> > see http://lists.openswan.org/pipermail/dev/2005-April/000844.html for the
> > problem description.]
> For the record, the crasher meantioned here is the one causing: ASSERTION FAILED at
> crypto.c:219: st->st_new_iv_len >= e->enc_blocksize

> > seem to suggest this. So it seems to be secure in the sense that only
> > authorized users can crash it. However, this is typically also seen as a DoS
> > (comparable to local privilege escalation bugs).
> Yes. This one, and the ones frim the IPsec Proto testsuite (that caused us to
> release openswan 2.4.3 and 2.4.4) can only crash pluto in phase2, so some form
> of authentiction has already taken place.

> > > At a first glance this doesn't smell like a security problem (but that
> > > depends on the answers above). Intercompatibility between older and newer
> > > versions is certainly desirable, but OTOH roadwarriors are under control of
> > > the local admin as well and can be forced to run stable on their notebooks
> > > as well.
> > True, but assuming an adversary, it can be a DoS for large gateways with many
> > roadwarriors. The logs should reveal the culprit, but it's still denial of
> > service.
> There are more bugs that should be applied to openswan-2.4.0. For instance the
> documented ones from the IPsec Proto testsuite that were released a while ago
> that caused the release of openswan 2.4.3 and 2.4.4.
> > > Upgrading to 2.4.5 isn't an option in either case, it has the potential to
> > > introduce more regressions and incompatibilities for existing setups, that
> > > it would fix in this specific use case.
> Openswan 2.4 is considered the "stable" tree. If you still think you want to
> cherry pick from those fixes, please look at the cvs mailinglist archive at
> http://lists.openswan.org/pipermail/cvs/ and see which commits you should apply.
> A quick browse tells me:
> http://lists.openswan.org/pipermail/cvs/2005-November/005580.html

Umh, could you give me an idea of what is fixed by this?

> http://lists.openswan.org/pipermail/cvs/2005-November/005557.html

That's a denial of service problem.

However, since the pluto daemon is restarted immediately, there
is no denial of service anymore.

> http://lists.openswan.org/pipermail/cvs/2005-November/005594.html

What is fixed by this one?

> http://lists.openswan.org/pipermail/cvs/2005-November/005593.html

And by this one?



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