sudo before 1.8.12 does not ensure that the TZ environment variable is associated with a zoneinfo file, which allows local users to open arbitrary files for read access (but not view file contents) by running a program within an sudo session, as demonstrated by interfering with terminal output, discarding kernel-log messages, or repositioning tape drives.
Exploitability
AV:LAC:LPR:LUI:NScope
S:UImpact
C:LI:NA:N3.3/CVSS:3.0/AV:L/AC:L/PR:L/UI:N/S:U/C:L/I:N/A:N