CVE-2026-59145

Technical Description

Data::Intern::Shared versions before 0.02 for Perl allow an out-of-bounds read via unvalidated slot, reverse and arena indices in si_idx_find.

The attach-time validator si_validate_header is thorough about the header and layout (magic, version, section offsets, total_size, count and arena_used) but does not validate the three arrays it then trusts. Every lookup in si_idx_find walks a triple indirection read straight from the mmap'd segment, arena[reverse[slots[i].id]], with no bound on slots[i].id against count, on the reverse[id] arena offset against arena_used, or on the arena record's length prefix.

A local peer that can write the backing file can leave the header valid while poisoning a slot id, a reverse offset or an arena length prefix, so an id_of, intern or string lookup dereferences the chain out of bounds; because string() returns a file-controlled length of bytes from the arena, adjacent process memory can be disclosed.

Remediation

Check the references section for vendor advisories, patches, and mitigation guidance. If immediate patching is not possible, review the CVSS vector to understand the attack surface and apply compensating controls such as network segmentation or access restrictions.

References