The overlayfs implementation in the linux kernel did not properly validate with respect to user namespaces the setting of file capabilities on files in an underlying file system. Due to the combination of unprivileged user namespaces along with a patch carried in the Ubuntu kernel to allow unprivileged overlay mounts, an attacker could use this to gain elevated privileges.
Metabase open source before 0.46.6.1 and Metabase Enterprise before 1.46.6.1 allow attackers to execute arbitrary commands on the server, at the server's privilege level. Authentication is not required for exploitation. The other fixed versions are 0.45.4.1, 1.45.4.1, 0.44.7.1, 1.44.7.1, 0.43.7.2, and 1.43.7.2.