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

Severity: high (CVSS 7.5 v3.1)
Exploited in the wild: not listed in CISA KEV
EPSS: 0.6% probability of exploitation in the next 30 days
Public exploit or detection template: yes
Published: 2026-07-10 · updated 2026-10-25
Weakness: CWE-770

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.

Affected products

qax-os excelize: before 2.11.0 — fixed in 2.11.0

How to fix

Upgrade to a fixed version: qax-os excelize 2.11.0. Check the vendor advisory for mitigations.

References

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