Perl versions through 5.43.10 have an integer overflow in S_measure_struct leading to an out-of-bounds heap read in pack and unpack. S_measure_struct adds each item's size times its repeat count to a running total with no overflow check, so a large repeat count in a pack or unpack template wraps the signed SSize_t total negative. The @, X, and x position codes then guard their moves with a signed length comparison that passes when the length is negative, advancing the buffer pointer out of bounds. A template derived from untrusted input can read heap memory past the buffer and return it to the caller.
History

Tue, 14 Jul 2026 14:30:00 +0000

Type Values Removed Values Added
Metrics cvssV3_1

{'score': 8.4, 'vector': 'CVSS:3.1/AV:L/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H'}

ssvc

{'options': {'Automatable': 'no', 'Exploitation': 'none', 'Technical Impact': 'total'}, 'version': '2.0.3'}


Mon, 13 Jul 2026 17:45:00 +0000

Type Values Removed Values Added
First Time appeared Shay
Shay perl
Vendors & Products Shay
Shay perl

Mon, 13 Jul 2026 16:30:00 +0000

Type Values Removed Values Added
Description Perl versions through 5.43.10 have an integer overflow in S_measure_struct leading to an out-of-bounds heap read in pack and unpack. S_measure_struct adds each item's size times its repeat count to a running total with no overflow check, so a large repeat count in a pack or unpack template wraps the signed SSize_t total negative. The @, X, and x position codes then guard their moves with a signed length comparison that passes when the length is negative, advancing the buffer pointer out of bounds. A template derived from untrusted input can read heap memory past the buffer and return it to the caller.
Title Perl versions through 5.43.10 have an integer overflow in S_measure_struct leading to an out-of-bounds heap read in pack and unpack
Weaknesses CWE-125
CWE-190
References

cve-icon MITRE

Status: PUBLISHED

Assigner: CPANSec

Published: 2026-07-13T15:38:20.728Z

Updated: 2026-07-14T13:34:42.360Z

Reserved: 2026-06-24T13:09:26.322Z

Link: CVE-2026-57432

cve-icon Vulnrichment

Updated: 2026-07-13T19:30:46.712Z

cve-icon NVD

No data.

cve-icon Redhat

No data.