Reference page — cumulative record through Monday, October 19, 2026 UTC. Reference pages update as the archive grows; only dated daily editions are immutable pages of record.

CVE-2026-107218

CVE-2026-107218MEDIUM

qax-os excelize — Excelize: RIGHT() on supplementary-plane text slices with a negative index and panics

  AV  AC  PR  UI  S  C  I  A   CVSS    EPSS   %ile   KEV
   N   L   N   N  U  N  N  L    5.3   .0029   20.0     —

AFFECTED
  Product   Versions                Fixed
  excelize  >= 2.10.1, <= 2.11.0 –  —

TIMELINE
  Oct 7   Reserved by GitHub_M
  Oct 7   Published (CNA: GitHub_M)
  Oct 13  EXPLOIT PUBLISHED — CVE-2026-107218 (qax-os excelize). Public exploit reference added.

CWE-129 · CNA: GitHub_M · CVSS v3.1 · 3 references · NVD status: Analyzed

Description

Excelize is a Go language library for reading and writing Microsoft Excel spreadsheets. From 2.10.1 to 2.11.0, RIGHT validates the requested length with UTF-16 code-unit counts but slices a rune array using Unicode code-point counts. RIGHT reaches leftRight through CalcCellValue, where countUTF16String validates one unit but utf8.RuneCountInString supplies the slice index in another. When RIGHT evaluates supplementary-plane text with a requested character count between the rune count and UTF-16 code-unit count, the inconsistent units produce a negative rune-slice index, allowing an attacker to panic during formula evaluation. No fixed version is available as of this review.

Lifecycle

Complete event history — 3 events, chronological
Date	Event	Detail
October 7, 2026	Reserved	Reserved by GitHub_M
October 7, 2026	Published	Published (CNA: GitHub_M)
October 13, 2026	EXPLOIT PUBLISHED	EXPLOIT PUBLISHED — CVE-2026-107218 (qax-os excelize). Public exploit reference added.

Affected

Affected products and packages — 1 row
Vendor	Product / Package	Ecosystem	Version introduced	Fixed
qax-os	excelize	—	>= 2.10.1, <= 2.11.0	—

Weaknesses

CWE-129

References (3)

https://github.com/qax-os/excelize/commit/ecd99d761fe0489f1ed308e2f7dc2e0502d1a396 [Patch]
https://github.com/qax-os/excelize/pull/2390 [Issue Tracking, Patch]
https://github.com/qax-os/excelize/security/advisories/GHSA-8jjq-8j9w-m2v6 [Exploit, Vendor Advisory]

Authoritative record: CVE-2026-107218 at cve.org

Vendors: qax-os

Weaknesses: CWE-129

About this page

This is a reference page, not a dated page of record. It assembles the complete lifecycle of CVE-2026-107218 from the CVE Program record, NVD enrichment, the CISA KEV catalog, EPSS, and OSV advisories. The box score's numbers (CVSS, EPSS, KEV status) are current as of Monday, October 19, 2026 UTC and are re-derived as the archive grows; only dated daily editions are immutable pages of record. The authoritative source for this identifier is cve.org.