Excelize: Unbounded Row Index Allocation in Worksheet Parser (checkSheet OOM/Panic DoS)

Exploitation

No confirmed exploitation recorded. Patch Next marks exploitation only from CISA KEV.

CVSS

7.5 · CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H

EPSS

• CVE-2026-54063: 0.61% estimated exploitation activity in the next 30 days; percentile 49.09 (FIRST EPSS, 2026-11-03). This is a model estimate, not proof of exploitation or customer exposure.

As published by the source; long descriptions are shortened.

Unbounded Row Index Allocation in Worksheet Parser (checkSheet OOM/Panic DoS) Summary 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. Details The vulnerable code path is triggered by calling GetCellValue (or any API that internally invokes workSheetReader) on an XLSX file containing a crafted worksheet row element. Data flow (source → sink): 1. excelize.go:186-193 — OpenReader reads attacker-controlled spreadsheet bytes. 2. excelize.go:216-223 —…

Published by the source

27 Jul 2026, 15:30 UTC

Last modified by the source

27 Jul 2026, 17:00 UTC

Source last checked

26 Oct 2026, 15:24 UTC

1. Revision 2 · amended · 26 Oct 2026

   Amended from ghsa record GHSA-h69g-9hx6-f3v4

2. Revision 1 · created · 24 Oct 2026

   Published from osv record GO-2026-5960

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# Patch Next advisory brief: CVE-2026-54063

Advisory: Excelize: Unbounded Row Index Allocation in Worksheet Parser (checkSheet OOM/Panic DoS)
IDs: CVE-2026-54063, GHSA-h69g-9hx6-f3v4
Record: https://patchnext.com/advisories/cve-2026-54063 (revision 2, source checked 26 Oct 2026, 15:24 UTC)
Inventory: none attached. This brief comes from a public page and does not say whether any deployment is affected.
Severity: High (CVSS 7.5)
Exploitation: no confirmed exploitation recorded. Patch Next confirms exploitation only from CISA KEV.
Vendor response: Vendor fix available; fixed versions by package: github.com/xuri/excelize/v2 2.11.0. A vendor fix does not mean a deployment is fixed.

## Affected components
- Go github.com/xuri/excelize/v2: affected < 2.11.0; fixed in 2.11.0

## Suggested inspection (read-only)
- Go github.com/xuri/excelize/v2: check the installed version with your package manager.

## Supported action
Upgrade each affected component to a fixed version on its release line. For a transitive dependency, upgrade the parent package or add an override or constraint, then regenerate the lockfile. Redeploy every environment that ran an affected version.

## Required regression checks
- Run the test suite and a production build.
- Exercise the features that depend on github.com/xuri/excelize/v2.
- Repeat the inspection and confirm that only fixed versions remain installed.

## Rollback considerations
- Keep the previous lockfile and deployment artifact. Rolling back reinstates the vulnerable version, so apply any documented mitigation while you fix forward.

## Unresolved questions
- Which deployments run an affected version?
- Exploitation status can change. Check again before lowering the priority.
- Mark the work resolved only after the fixed version is verified in production.

## Sources
- Verified: https://osv.dev/vulnerability/GO-2026-5960 (OSV record GO-2026-5960 lists affected ranges: Go github.com/xuri/excelize/v2 >=0 <2.11.0 (fixed))
- Verified: https://github.com/advisories/GHSA-h69g-9hx6-f3v4 (GitHub-reviewed advisory GHSA-h69g-9hx6-f3v4 lists affected ranges: Go github.com/xuri/excelize/v2 >=0 <2.11.0)

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