Vulnerability · Published Oct 7, 2026 · Assigned by GitHub_M
CVE-2026-107224Excelize: A Zip64 uncompressed-size of 2^63 panics OpenFile/OpenReader
Medium 6.5
In plain English
A medium-severity integer overflow in excelize from qax-os. Proof-of-concept exploit code is public. The chance it is exploited in the next 30 days is estimated at 0.3% (higher than 24% of all known vulnerabilities). Fixed versions are available - upgrade the affected package.
Official 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.
Affected packages & fixed versions
| Ecosystem | Package | Fixed in | Advisory |
|---|---|---|---|
| Go | github.com/360EntSecGroup-Skylar/excelize/v2 | no fix listed | GO-2026-6679 |
| Go | github.com/xuri/excelize/v2 | 2.11.1-0.20260805032953-db93f8d89de7 | GHSA-fw94-4wwp-w8pw |
| Go | github.com/xuri/excelize/v2 | 2.11.1-0.20260805032953-db93f8d89de7 | GO-2026-6679 |
Affected products (as reported)
Weakness: CWE-190, CWE-681 · Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:N/I:N/A:H
References
- https://github.com/qax-os/excelize/security/advisories/GHSA-fw94-4wwp-w8pw x_refsource_CONFIRM
- https://github.com/qax-os/excelize/pull/2369 x_refsource_MISC
- https://github.com/qax-os/excelize/commit/db93f8d89de71589069a54d1b998af02e3c5f7cd x_refsource_MISC