Follow @Openwall on Twitter for new release announcements and other news
[<prev] [next>] [thread-next>] [day] [month] [year] [list]
Date: Wed, 13 Mar 2013 16:39:56 +0100
From: Sebastian Krahmer <>
Subject: CLONE_NEWUSER|CLONE_FS root exploit


Seems like CLONE_NEWUSER|CLONE_FS might be a forbidden
During evaluating the new user namespace thingie, it turned out
that its trivially exploitable to get a (real) uid 0,
as demonstrated here:

The trick is to setup a chroot in your CLONE_NEWUSER,
but also affecting the parent, which is running
in the init_user_ns, but with the chroot shared.
Then its trivial to get a rootshell from that.

Tested on a openSUSE12.1 with a custom build 3.8.2 (x86_64).

I hope I didnt make anything wrong, mixing up the UIDs,
or disabled important checks during kernel build on my test
system. ;)



~ perl
~ $_='print"\$_=\47$_\47;eval"';eval
~ - SuSE Security Team

Powered by blists - more mailing lists

Please check out the Open Source Software Security Wiki, which is counterpart to this mailing list.

Confused about mailing lists and their use? Read about mailing lists on Wikipedia and check out these guidelines on proper formatting of your messages.