Three security flaws are affecting the Ubuntu 16.04 LTS (Xenial Xerus) operating system and later versions, as well as any derivative. The first one is a race condition in Liux kernel’s audit subsystems, which could allow a local attacker to interrupt system-call auditing or damage the audit logs. The second security issue is related to Linux kernel’s KVM (Kernel-based Virtual Machine) hypervisor implementation, which didn’t work correctly on PPC64 (PowerPC 64-bit) and PowerPC (PPC) platforms, thus allowing an unprivileged attacker to cause a CPU lockup in the host operating system.