CVE-2026-128338
ExcelJS through 4.4.0 Memory Exhaustion via Unbounded Worksheet Column Range
exceljs through 4.4.0 contains a memory exhaustion vulnerability that allows attackers to crash applications by supplying a worksheet col element with an unbounded max attribute. Attackers can craft a small workbook with a huge max value, causing xlsx.load() to allocate hundreds of millions of Column objects and abort the process with an uncatchable heap out-of-memory error.
Fixes and workarounds
No remediation reported in collected sources.
Missing remediation information is not evidence that no patch exists.
Affected products and versions
| Product | Versions | Authority |
|---|---|---|
| exceljs exceljs exceljs
npm |
≥ 0; ≤ 4.4.0 (affected, semver)
Other versions: unaffected |
CNA: VulnCheck |
Version ranges are source assertions. Check the vendor advisory and your installed configuration before determining exposure.
CVSS assessments
| Version / score | Vector | Authority |
|---|---|---|
| 4.0 / 8.7 high |
CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:N/VI:N/VA:H/SC:N/SI:N/SA:N | CNA: VulnCheck |
| 3.1 / 7.5 high |
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H | CNA: VulnCheck |
| 4.0 / 8.7 high |
CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:N/VI:N/VA:H/SC:N/SI:N/SA:N/E:X/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:X | NVD: [email protected] |
| 3.1 / 7.5 high |
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H | NVD: [email protected] |
Exploit evidence
No exploit evidence in collected sources. This is not proof of no exploitation.
References
- https://github.com/exceljs/exceljsCNA: VulnCheck · product
- https://github.com/mateocallec/exceljs-hardened/security/advisories/GHSA-w57r-3mm6-w6g7CNA: VulnCheck · third-party-advisory
- https://github.com/exceljs/exceljs/blob/v4.4.0/lib/doc/column.js#L307-L316CNA: VulnCheck · technical-description
- https://github.com/exceljs/exceljs/blob/v4.4.0/lib/xlsx/xform/sheet/col-xform.js#L43-L47CNA: VulnCheck · technical-description
- https://www.vulncheck.com/advisories/exceljs-through-4.4.0-memory-exhaustion-via-unbounded-worksheet-column-rangeCNA: VulnCheck · third-party-advisory
- https://github.com/exceljs/exceljs[email protected]
- https://github.com/exceljs/exceljs/blob/v4.4.0/lib/doc/column.js#L307-L316[email protected]
- https://github.com/exceljs/exceljs/blob/v4.4.0/lib/xlsx/xform/sheet/col-xform.js#L43-L47[email protected]
- https://github.com/mateocallec/exceljs-hardened/security/advisories/GHSA-w57r-3mm6-w6g7[email protected]
- https://www.vulncheck.com/advisories/exceljs-through-4.4.0-memory-exhaustion-via-unbounded-worksheet-column-range[email protected]
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