Excelize is a Go language library for reading and writing Microsoft Excel spreadsheets. From 2.1.0 to 2.11.0, a Zip64 uncompressed size with the high bit set is converted from uint64 to a negative int64 before signed size-limit checks and allocation. ReadZipReader obtains UncompressedSize64 through FileInfo.Size and passes the wrapped negative value to readFile. When a crafted Zip64 entry declares an uncompressed size from 2^63 through 2^64-1 and the workbook is opened, the negative size bypasses unzip limits and reaches make as a negative capacity, allowing an attacker to panic during workbook opening. No fixed version is available as of this review.
Advisories
Source ID Title
Github GHSA Github GHSA GHSA-fw94-4wwp-w8pw Excelize: A Zip64 uncompressed-size of 2^63 panics OpenFile/OpenReader
Fixes

Solution

No solution given by the vendor.


Workaround

No workaround given by the vendor.

History

Wed, 07 Oct 2026 21:00:00 +0000

Type Values Removed Values Added
First Time appeared Qax-os
Qax-os excelize
Vendors & Products Qax-os
Qax-os excelize

Wed, 07 Oct 2026 20:30:00 +0000

Type Values Removed Values Added
Metrics ssvc

{'options': {'Automatable': 'no', 'Exploitation': 'poc', 'Technical Impact': 'partial'}, 'version': '2.0.3'}


Wed, 07 Oct 2026 19:00:00 +0000

Type Values Removed Values Added
Description Excelize is a Go language library for reading and writing Microsoft Excel spreadsheets. From 2.1.0 to 2.11.0, a Zip64 uncompressed size with the high bit set is converted from uint64 to a negative int64 before signed size-limit checks and allocation. ReadZipReader obtains UncompressedSize64 through FileInfo.Size and passes the wrapped negative value to readFile. When a crafted Zip64 entry declares an uncompressed size from 2^63 through 2^64-1 and the workbook is opened, the negative size bypasses unzip limits and reaches make as a negative capacity, allowing an attacker to panic during workbook opening. No fixed version is available as of this review.
Title Excelize: A Zip64 uncompressed-size of 2^63 panics OpenFile/OpenReader
Weaknesses CWE-190
CWE-681
References
Metrics cvssV3_1

{'score': 6.5, 'vector': 'CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:N/I:N/A:H'}


Projects

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cve-icon MITRE

Status: PUBLISHED

Assigner: GitHub_M

Published:

Updated: 2026-10-07T19:30:13.733Z

Reserved: 2026-10-07T14:34:14.816Z

Link: CVE-2026-107224

cve-icon Vulnrichment

Updated: 2026-10-07T19:30:07.190Z

cve-icon NVD

Status : Received

Published: 2026-10-07T19:17:35.140

Modified: 2026-10-07T20:17:11.713

Link: CVE-2026-107224

cve-icon Redhat

No data.

cve-icon OpenCVE Enrichment

Updated: 2026-10-07T20:45:07Z

Weaknesses