The string component in the GNU C Library (aka glibc or libc6) through 2.28, when running on the x32 architecture, incorrectly attempts to use a 64-bit register for size_t in assembly codes, which can lead to a segmentation fault or possibly unspecified other impact, as demonstrated by a crash in __memmove_avx_unaligned_erms in sysdeps/x86_64/multiarch/memmove-vec-unaligned-erms.S during a memcpy.