The common changes of both releases are fixes for two potential, rare hang and crash storage issues, both of which occurred under rare circumstances. Notable here is that the rare crash could occur when during various file maintenance operations, such as merging of snapshots, or when asynchronous I/O was disabled. Additionally, both VirtualBox 5.1.22 and VirtualBox 5.0.40 fix a software virtualization issue on Solaris hosts and repair an ALSA (Advanced Linux Sound Architecture) backend regression on Linux hosts, from VirtualBox 5.1.20 and VirtualBox 5.0.38, along with the loading of OpenGL libraries on specific hosts.