CVE-2026-88351

Integer Overflow in MPack Node API Causes Heap Buffer Overflow on 32-bit Platforms

Published Sep 24, 2026 CVSS 3.1 · 9.8 Critical EPSS < 1% KEV · Not listed
Description
An integer overflow vulnerability exists in the MPack Node API in MPack 1.1.1 on 32-bit platforms. When parsing a specially crafted MessagePack array32 or map32 object with an excessively large element count, the page allocation size calculation in mpack_tree_parse_children() can overflow size_t and produce an undersized allocation. Subsequent parsing writes mpack_node_data_t records beyond the allocated heap buffer, resulting in heap-buffer-overflow, memory corruption, and denial of service.

Remediation

No solution or workaround provided in the CVE record

Tracking

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Advisories

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History
Type Values Removed Values Added
Title Integer Overflow in MPack Node API Causes Heap Buffer Overflow on 32-bit Platforms
Type Values Removed Values Added
Metrics ssvc

{'options': {'Automatable': 'yes', 'Exploitation': 'poc', 'Technical Impact': 'total'}, 'version': '2.0.3'}

Type Values Removed Values Added
Weaknesses CWE-190
Metrics cvssV3_1

{'score': 9.8, 'vector': 'CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H'}

Type Values Removed Values Added
First Time appeared Ludocode
Ludocode mpack
Vendors & Products Ludocode
Ludocode mpack
Type Values Removed Values Added
Description An integer overflow vulnerability exists in the MPack Node API in MPack 1.1.1 on 32-bit platforms. When parsing a specially crafted MessagePack array32 or map32 object with an excessively large element count, the page allocation size calculation in mpack_tree_parse_children() can overflow size_t and produce an undersized allocation. Subsequent parsing writes mpack_node_data_t records beyond the allocated heap buffer, resulting in heap-buffer-overflow, memory corruption, and denial of service.
References
Weaknesses

Sources

Status
PUBLISHED
Assigner
mitre
Published
Updated
Sep 25, 2026, 6:09 PM
Reserved
Sep 10, 2026, 12:00 AM
Status
Deferred
Published
Sep 24, 2026, 3:17 PM
Modified
Sep 25, 2026, 6:17 PM