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

Published Jul 21, 2026 CVSS 3.1 · 9.1 Critical EPSS < 1% KEV · Not listed
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

Vendor Solution

Upgrade to Data::Intern::Shared 0.02 or later, which bounds the slot id, the reverse offset and the record length before each dereference and caps the hash-slot probe.


Vendor Workaround

For deployments that cannot upgrade to 0.02, place the backing file in a directory writable only by the owning user, so a local peer cannot tamper with the slot, reverse and arena contents the lookup path reads.

Tracking

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Advisories

No advisories available
History
Type Values Removed Values Added
First Time appeared Egor
Egor data::intern::shared
Vendors & Products Egor
Egor data::intern::shared
Type Values Removed Values Added
Metrics cvssV3_1

{'score': 9.1, 'vector': 'CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:N/A:H'}

ssvc

{'options': {'Automatable': 'yes', 'Exploitation': 'none', 'Technical Impact': 'partial'}, 'version': '2.0.3'}

Type Values Removed Values Added
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.
Title 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
Weaknesses CWE-125
References
Weaknesses

Sources

Status
PUBLISHED
Assigner
CPANSec
Published
Updated
Jul 22, 2026, 7:35 PM
Reserved
Jul 2, 2026, 4:24 PM
Status
Deferred
Published
Jul 21, 2026, 8:17 PM
Modified
Oct 24, 2026, 7:10 PM