An integer overflow vulnerability exists in the MPack Node API in MPack 1.1.1 on 32-bit platforms. (CVE-2026-88351)
Description
An integer overflow vulnerability in the MPack Node API in MPack 1.1.1 on 32-bit platforms can cause heap-buffer-overflow, memory corruption, and denial of service when parsing crafted MessagePack array32 or map32 objects with large element counts.
CVSS v3.1
Score 9.8critical
Affected software
pkg:deb/ubuntu/mpack?arch=source&distro=xenialpkg:deb/ubuntu/mpack?arch=source&distro=bionicpkg:deb/ubuntu/mpack?arch=source&distro=focalpkg:deb/ubuntu/mpack?arch=source&distro=jammypkg:deb/ubuntu/mpack?arch=source&distro=noblepkg:deb/ubuntu/mpack?arch=source&distro=stonkingpkg:deb/ubuntu/mpack?arch=source&distro=resoluteRun on your own infrastructure? Check whether these packages are installed with threat-finder — our free open-source scanner.
AI-Powered Analysis
Machine-generated threat intelligence
Technical Analysis
CVE-2026-88351 describes an integer overflow vulnerability in the MPack Node API in version 1.1.1 on 32-bit platforms. The vulnerability occurs during parsing of specially crafted MessagePack array32 or map32 objects with excessively large element counts. The calculation of the page allocation size in the function mpack_tree_parse_children() can overflow the size_t type, leading to an undersized heap allocation. Subsequent parsing writes beyond the allocated buffer, causing heap-buffer-overflow, memory corruption, and denial of service.
Potential Impact
Successful exploitation can result in heap-buffer-overflow and memory corruption, potentially leading to denial of service. The CVSS v3.1 score is 9.8 (critical), indicating high impact on confidentiality, integrity, and availability.
Mitigation Recommendations
Patch status is not yet confirmed — check the vendor advisory for current remediation guidance.
Technical Details
- Gcve Source
- db.gcve.eu
- Osv Id
- UBUNTU-CVE-2026-88351
- Osv Schema Version
- 1.7.0
- Ecosystems
- ["Ubuntu:16.04:LTS","Ubuntu:18.04:LTS","Ubuntu:20.04:LTS","Ubuntu:22.04:LTS","Ubuntu:24.04:LTS","Ubuntu:26.10","Ubuntu:26.04:LTS"]
- Cvss Version
- 3.1
- State
- PUBLISHED
Threat ID: 6ad3f5432cdf04f65665864a
Added to database: 10/17/2026, 22:22:59 UTC
Last enriched: 10/17/2026, 23:19:50 UTC
Last updated: 10/17/2026, 23:19:50 UTC
Views: 3
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