/usr/share/zoneinfo/posix/Etc/ is in tzdata 2018e-0+deb8u1.
This file is owned by root:root, with mode 0o755.
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/usr/share/zoneinfo/posix/Etc/GMT
/usr/share/zoneinfo/posix/Etc/GMT+0
/usr/share/zoneinfo/posix/Etc/GMT+1
/usr/share/zoneinfo/posix/Etc/GMT+10
/usr/share/zoneinfo/posix/Etc/GMT+11
/usr/share/zoneinfo/posix/Etc/GMT+12
/usr/share/zoneinfo/posix/Etc/GMT+2
/usr/share/zoneinfo/posix/Etc/GMT+3
/usr/share/zoneinfo/posix/Etc/GMT+4
/usr/share/zoneinfo/posix/Etc/GMT+5
/usr/share/zoneinfo/posix/Etc/GMT+6
/usr/share/zoneinfo/posix/Etc/GMT+7
/usr/share/zoneinfo/posix/Etc/GMT+8
/usr/share/zoneinfo/posix/Etc/GMT+9
/usr/share/zoneinfo/posix/Etc/GMT-0
/usr/share/zoneinfo/posix/Etc/GMT-1
/usr/share/zoneinfo/posix/Etc/GMT-10
/usr/share/zoneinfo/posix/Etc/GMT-11
/usr/share/zoneinfo/posix/Etc/GMT-12
/usr/share/zoneinfo/posix/Etc/GMT-13
/usr/share/zoneinfo/posix/Etc/GMT-14
/usr/share/zoneinfo/posix/Etc/GMT-2
/usr/share/zoneinfo/posix/Etc/GMT-3
/usr/share/zoneinfo/posix/Etc/GMT-4
/usr/share/zoneinfo/posix/Etc/GMT-5
/usr/share/zoneinfo/posix/Etc/GMT-6
/usr/share/zoneinfo/posix/Etc/GMT-7
/usr/share/zoneinfo/posix/Etc/GMT-8
/usr/share/zoneinfo/posix/Etc/GMT-9
/usr/share/zoneinfo/posix/Etc/GMT0
/usr/share/zoneinfo/posix/Etc/Greenwich
/usr/share/zoneinfo/posix/Etc/UCT
/usr/share/zoneinfo/posix/Etc/UTC
/usr/share/zoneinfo/posix/Etc/Universal
/usr/share/zoneinfo/posix/Etc/Zulu