CVE-2026-128340

EUVD-2026-125037
ExcelJS through 4.4.0 contains a memory exhaustion vulnerability that allows attackers to crash applications by supplying a workbook with an oversized defined-name range. DefinedNames.addEx expands ranges such as S!$A$1:$XFD$1048576 from xl/workbook.xml cell by cell, causing an uncatchable fatal heap out-of-memory error during xlsx.load().
ProviderTypeBase ScoreAtk. VectorAtk. ComplexityPriv. RequiredVector
VulnCheckCNA
7.5 HIGH
NETWORK
LOW
NONE
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H
Base Score
CVSS 3.x
EPSS Score
Percentile: 50.74%
Early Detection
Affected products identified ahead of NVD analysis through intelligence sources (CNA/ADP records, vendor advisories, Enginsight analysis).
VendorProductVersionSource
exceljs_projectexceljs
𝑥
≤ 4.4.0
CNA
Common Weakness Enumeration
References
https://github.com/exceljs/exceljs
https://github.com/exceljs/exceljs/blob/v4.4.0/lib/doc/defined-names.js#L182-L193
https://github.com/exceljs/exceljs/blob/v4.4.0/lib/utils/cell-matrix.js#L28-L37
https://github.com/mateocallec/exceljs-hardened/security/advisories/GHSA-qvh4-wwpm-ggc8
https://www.vulncheck.com/advisories/exceljs-through-4.4.0-memory-exhaustion-via-oversized-defined-name-range
https://github.com/mateocallec/exceljs-hardened/security/advisories/GHSA-qvh4-wwpm-ggc8