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
Created bubblewrap tracking bugs for this issue: Affects: epel-7 [bug 1411815] Affects: fedora-all [bug 1411814]
We decided not to change bubblewrap for this; see https://github.com/projectatomic/bubblewrap/pull/150 Effectively it's something software which *uses* flatpak has to choose how to handle. (Also really the kernel should make it easy to disallow)