EUVD-2026-46369

Data::Buffer::Shared versions before 0.05 for Perl create a world-readable mmap backing file and open it without ONOFOLLOW. The segment is created in bufgeneric.h with openpath, ORDWR|OCREAT|OEXCL, 0666. OEXCL blocks a pre-seeded file on create, but the mode is 0666, so under the default umask 02...