/usr/share/gimp/2.0/palettes/ is in gimp-data 2.8.22-1.
This file is owned by root:root, with mode 0o755.
..
/usr/share/gimp/2.0/palettes/Bears.gpl
/usr/share/gimp/2.0/palettes/Bgold.gpl
/usr/share/gimp/2.0/palettes/Blues.gpl
/usr/share/gimp/2.0/palettes/Borders.gpl
/usr/share/gimp/2.0/palettes/Browns_And_Yellows.gpl
/usr/share/gimp/2.0/palettes/Caramel.gpl
/usr/share/gimp/2.0/palettes/Cascade.gpl
/usr/share/gimp/2.0/palettes/China.gpl
/usr/share/gimp/2.0/palettes/Coldfire.gpl
/usr/share/gimp/2.0/palettes/Cool_Colors.gpl
/usr/share/gimp/2.0/palettes/Cranes.gpl
/usr/share/gimp/2.0/palettes/Dark_pastels.gpl
/usr/share/gimp/2.0/palettes/Default.gpl
/usr/share/gimp/2.0/palettes/Ega.gpl
/usr/share/gimp/2.0/palettes/Firecode.gpl
/usr/share/gimp/2.0/palettes/Gold.gpl
/usr/share/gimp/2.0/palettes/GrayViolet.gpl
/usr/share/gimp/2.0/palettes/Grayblue.gpl
/usr/share/gimp/2.0/palettes/Grays.gpl
/usr/share/gimp/2.0/palettes/Greens.gpl
/usr/share/gimp/2.0/palettes/Hilite.gpl
/usr/share/gimp/2.0/palettes/Khaki.gpl
/usr/share/gimp/2.0/palettes/Lights.gpl
/usr/share/gimp/2.0/palettes/Muted.gpl
/usr/share/gimp/2.0/palettes/Named_Colors.gpl
/usr/share/gimp/2.0/palettes/News3.gpl
/usr/share/gimp/2.0/palettes/Op2.gpl
/usr/share/gimp/2.0/palettes/Paintjet.gpl
/usr/share/gimp/2.0/palettes/Pastels.gpl
/usr/share/gimp/2.0/palettes/Plasma.gpl
/usr/share/gimp/2.0/palettes/Reds.gpl
/usr/share/gimp/2.0/palettes/Reds_And_Purples.gpl
/usr/share/gimp/2.0/palettes/Royal.gpl
/usr/share/gimp/2.0/palettes/Tango.gpl
/usr/share/gimp/2.0/palettes/Topographic.gpl
/usr/share/gimp/2.0/palettes/Visibone.gpl
/usr/share/gimp/2.0/palettes/Visibone_2.gpl
/usr/share/gimp/2.0/palettes/Volcano.gpl
/usr/share/gimp/2.0/palettes/Warm_Colors.gpl
/usr/share/gimp/2.0/palettes/Web.gpl