Sudo before 1.9.17p1 allows local users to obtain root access because /etc/nsswitch.conf from a user-controlled directory is used with the --chroot option.
Exploitability
AV:LAC:LPR:NUI:NScope
S:CImpact
C:HI:HA:H9.3/CVSS:3.1/AV:L/AC:L/PR:N/UI:N/S:C/C:H/I:H/A:H