/usr/include/X11/bitmaps/cross_weave is in xbitmaps 1.1.1-2.
This file is owned by root:root, with mode 0o644.
The actual contents of the file can be viewed below.
| 1 2 3 4 5 6 | #define cross_weave_width 16
#define cross_weave_height 16
static char cross_weave_bits[] = {
   0x55, 0x55, 0x88, 0x88, 0x55, 0x55, 0x22, 0x22, 0x55, 0x55, 0x88, 0x88,
   0x55, 0x55, 0x22, 0x22, 0x55, 0x55, 0x88, 0x88, 0x55, 0x55, 0x22, 0x22,
   0x55, 0x55, 0x88, 0x88, 0x55, 0x55, 0x22, 0x22};
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