Bubblewrap (bwrap) before version 0.4.1, if installed in setuid mode and the kernel supports unprivileged user namespaces, then the bwrap --userns2 option can be used to make the setuid process keep running as root while being traceable. This can in turn be used to gain root permissions. Note that this only affects the combination of bubblewrap in setuid mode (which is typically used when unprivileged user namespaces are not supported) and the support of unprivileged user namespaces. Known to be affected are: Debian testing/unstable, if unprivileged user namespaces enabled (not default) Debian buster-backports, if unprivileged user namespaces enabled (not default) Arch if using linux-hardened, if unprivileged user namespaces enabled (not default) Centos 7 flatpak COPR, if unprivileged user namespaces enabled (not default) This has been fixed in the 0.4.1 release, and all affected users should update.

When executing a program via the bubblewrap sandbox, the nonpriv session can escape to the parent session by using the TIOCSTI ioctl to push characters into the terminal's input buffer, allowing an attacker to escape the sandbox.

References:

https://bugs.debian.org/cgi-bin/bugreport.cgi?bug=850702

Upstream bugs:

https://github.com/projectatomic/bubblewrap/issues/142 https://github.com/projectatomic/bubblewrap/pull/143

Upstream patch:

https://github.com/projectatomic/bubblewrap/commit/d7fc532c42f0e9bf427923bab85433282b3e5117

bubblewrap.c in Bubblewrap before 0.3.3 misuses temporary directories in /tmp as a mount point. In some particular configurations (related to XDGRUNTIMEDIR), a local attacker may abuse this flaw to prevent other users from executing bubblewrap or potentially execute code.

Once docker containers register themselves to systemd-machined by oci-register-machine, any unprivileged user could run machinectl to list every single container running in the host even if the containers do not belong to this user (including containers belong to the root user), and access sensitive information associated with any individual container including its internal IP address, OS version, running processes, and file path for its rootfs.

$ machinectl status cc8d10c7b9892b75843d200d54d34a3a cc8d10c7b9892b75843d200d54d34a3a(63633864313063376239383932623735) Since: Mon 2016-07-25 17:55:36 UTC; 34s ago Leader: 43494 (sleep) Service: docker; class container Root: /var/mnt/overlay/overlay/0429684e3da515ae4f11b8514c7b20f759613 Address: 172.17.0.2 fe80::42:acff:fe11:2 OS: Red Hat Enterprise Linux Server 7.2 (Maipo) Unit: docker-cc8d10c7b9892b75843d200d54d34a3a9435fe0f65527c254ebfd2d └─43494 sleep 3000

CVE request:

http://seclists.org/oss-sec/2016/q3/156