A vulnerability exists in the BusyBox passwd and group file parser in libpwdgrp/pwd_grp.c. The tokenize() function trims trailing whitespace via overlapping_strcpy() but continues to reference the stale *end pointer, causing tokenize_end to be too large. This under-allocates in parse_common(), and convert_to_struct() then writes gr_mem[] pointers past the end of the heap allocation.

Triggering the vulnerability requires injecting malformed entries with whitespace before commas into /etc/group, then invoking any applet that calls getgrnam().