CVE-2026-59145
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.
What this means
- Exposure
- Exploitable remotely over the network, without authentication and with no action from the victim.
- Impact
- An attacker can read sensitive data and take the service offline.
- Weakness
- An out-of-bounds read exposes adjacent memory, often leftover secrets.
- Likelihood
- Its EPSS score stays low: nothing points to imminent exploitation, which is no reason to leave it unpatched.
What to doPatch without waiting for the next scheduled cycle. Start with the instances exposed to the internet.
Read automatically from the CVSS vector, the weakness type (CWE) and the EPSS score. The technical description above remains the one published by NIST.