I like the property option as a stopgap. Should we add a programatic option so that programmers can also control this on a per invoker basis?
Gary On Nov 8, 2015 6:43 AM, "Jochen Wiedmann" <jochen.wiedm...@gmail.com> wrote: > I like the property based approach. In particular, because we can > evaltuate that property within > > private void readObject > > Or, in other words: We can ship a jar that has the vulnerability > disabled by default (property isn't set). However, if the user > attempts to deserialize an InvokerTransformer, he or she gets a clear > and loud exception, that advices what to do (set the property). Should > be a solution that makes everyone happy in the medium term. > > Jochen > > > On Sun, Nov 8, 2015 at 3:30 PM, sebb <seb...@gmail.com> wrote: > > On 8 November 2015 at 12:32, Mark Thomas <ma...@apache.org> wrote: > >> On 08/11/2015 10:18, Thomas Neidhart wrote: > >>> On 11/07/2015 11:19 AM, Mark Thomas wrote: > >>>> On 07/11/2015 10:13, Thomas Neidhart wrote: > >>>>> On 11/07/2015 04:25 AM, Bernd Eckenfels wrote: > >>>>>> Hello, > >>>>>> > >>>>>> I tried to raise that concern in the message already, but it is > probably > >>>>>> worth repeating it explicitly: this is not a real bug > >>>>>> in the Commons-Collection class, and it might not be worse fixing > it, as > >>>>>> there are possibly tons of other vectors. This was also addressed > by the > >>>>>> original authors in the talk and even here on Twitter: > >>>>>> > >>>>>> https://twitter.com/gebl/status/662754611304996866 > >>>>>> > >>>>>> however, as the "foxglove" article shows, people still point at the > >>>>>> apache project, and after all it is good pratice to reduce > footprints > >>>>>> and attack surfaces. > >>>>> > >>>>> it is clear that the InvokerTransformer by itself does not have a > bug, > >>>>> but due to the way how java serialization is applied and considering > the > >>>>> fact that at least collections-3.2.1 is used *a lot* it would make > sense > >>>>> to provide a hardened version of collections to give people a chance > to > >>>>> easily avoid this line of attack in their application. > >>>>> > >>>>> Instead of removing the class we could prevent de-serialization of > it in > >>>>> the hardened jar. This would not break b/c and it is very unlikely > that > >>>>> the InvokerTransformer is serialized in legit ways. > >>>> > >>>> Rather than having hardened vs unhardened JARs, it would probably be > >>>> better to use a system property to enable/disable the behaviour. I > don't > >>>> know the code or the vulnerability well enough to know exactly where > to > >>>> put this switch so it prevents the attack but has minimal impact on > >>>> other uses. > >>> > >>> my idea was to have a binary compatible drop-in replacement that does > >>> not require any configuration, so that people that happen to have > >>> commons-collections 3.2.1 in their classpath can replace it with a > >>> hardened version. > >>> > >>> But I am open to other suggestions, in the end it is important to do > >>> what affected users would like to have to mitigate the problem. > >> > >> My main concern with a hardened JAR is that, while with just this > >> vulnerability, we end up with two JARs but how many JARs will we end up > >> with 3 or 4 vulnerabilities down the line. Particularly when fixing a > >> vulnerability means breaking functionality. I think system properties > >> scale better. > > > > But is there a use case for partially hardened jars? > > Surely if there are additional vulnerabilities they need to be fixed as > well? > > > > Using system properties simpifies things for Commons developers, > > however it makes it harder for consumers, as they have to ensure that > > the property is set. > > This may be hard to check if the jar is part of a large system. > > > > Though it would allow for certain vulnerabilities to be disabled by > > default (i.e.one has set a property to enable the risky code - [*]) > > and others only on demand. > > > > [*] This approach is already taken by the JDK with > > sun.net.http.allowRestrictedHeaders > > See: http://bugs.java.com/bugdatabase/view_bug.do?bug_id=6996110 > > > >> Mark > >> > >> > >> --------------------------------------------------------------------- > >> To unsubscribe, e-mail: dev-unsubscr...@commons.apache.org > >> For additional commands, e-mail: dev-h...@commons.apache.org > >> > > > > --------------------------------------------------------------------- > > To unsubscribe, e-mail: dev-unsubscr...@commons.apache.org > > For additional commands, e-mail: dev-h...@commons.apache.org > > > > > > -- > The next time you hear: "Don't reinvent the wheel!" > > > http://www.keystonedevelopment.co.uk/wp-content/uploads/2014/10/evolution-of-the-wheel-300x85.jpg > > --------------------------------------------------------------------- > To unsubscribe, e-mail: dev-unsubscr...@commons.apache.org > For additional commands, e-mail: dev-h...@commons.apache.org > >
