An intended access restriction in snapd could be bypassed by strict mode snaps on 64 bit architectures.
The snapd default seccomp filter for strict mode snaps blocks the use of the ioctl() system call when used with TIOCSTI as the second argument to the system call. Jann Horn discovered that this restriction could be circumvented on 64 bit architectures. A malicious snap could exploit this to bypass intended access restrictions to insert characters into the terminal’s input queue. On Ubuntu, snapd typically will have already automatically refreshed itself to snapd 2.37.4 which is unaffected.
21 March 2019
A security issue affects these releases of Ubuntu and its derivatives:
An intended access restriction in snapd could be bypassed by strict mode snaps on 64 bit architectures.
The snapd default seccomp filter for strict mode snaps blocks the use of the ioctl() system call when used with TIOCSTI as the second argument to the system call. Jann Horn discovered that this restriction could be circumvented on 64 bit architectures. A malicious snap could exploit this to bypass intended access restrictions to insert characters into the terminal’s input queue. On Ubuntu, snapd typically will have already automatically refreshed itself to snapd 2.37.4 which is unaffected.
The problem can be corrected by updating your system to the following package versions:
To update your system, please follow these instructions: https://wiki.ubuntu.com/Security/Upgrades.
In general, a standard system update will make all the necessary changes.
Vulmon