NULL pointer dereference in Qax-Os Excelize

CVE-2026-107222

Excelize is a Go language library for reading and writing Microsoft Excel spreadsheets. From 2.7.0 to 2.11.0, conditional-format extraction indexes required child slices or dereferences an optional colorScale child without validating malformed rule structure. GetConditionalFormats reaches extractCondFmtCellIs and also indexes ColorScale.Cfvo, DataBar.Cfvo, and DataBar.Color without complete structural checks. When a crafted worksheet supplies a cellIs, dataBar, or colorScale rule missing expected children and the application calls GetConditionalFormats, missing formula, color, value-object, or colorScale data reaches an out-of-range index or nil dereference, allowing an attacker to panic and terminate an unprotected process. No fixed version is available as of this review.

Published .

CVSS v3 metric

CVSS v3 base score 6.5 (Medium). Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:N/I:N/A:H.

EPSS exploit prediction

No EPSS score from FIRST.org yet. New CVEs usually get one within a few days; no score means no signal yet, not low risk. How EPSS works.

Affected products

Weakness classification (CWE)

References

Frequently asked questions

What is CVE-2026-107222?
CVE-2026-107222 is a medium-severity vulnerability in Qax-Os Excelize, classified under Improper Validation of Array Index. CVSS score: 6.5/10. Published 2026-10-07.
How severe is CVE-2026-107222?
Medium severity. CVSS v3 base score is 6.5 out of 10.