CVE-2026-128341
ExcelJS through 4.4.0 Denial of Service via Oversized Data Validation sqref
CVSS Score
7.5
EPSS Score
0.0%
EPSS Percentile
0th
ExcelJS through 4.4.0 contains a resource exhaustion vulnerability in data-validations-xform.js that allows attackers to exhaust CPU and memory by supplying unbounded sqref ranges. Attackers can provide a small crafted workbook with a sqref of A1:XFD1048576 to make xlsx.load() iterate billions of addresses, blocking the event loop and crashing the process with an uncatchable out-of-memory error.
| CWE | CWE-770 |
| Vendor | exceljs |
| Product | exceljs |
| Published | Nov 13, 2026 |
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CVSS v3 Breakdown
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H Attack Vector
Network
Attack Complexity
Low
Privileges Required
None
User Interaction
None
Scope
Unchanged
Confidentiality
None
Integrity
None
Availability
High
Affected Versions
exceljs / exceljs
0 ≤ 4.4.0
References
github.com: https://github.com/exceljs/exceljs github.com: https://github.com/mateocallec/exceljs-hardened/security/advisories/GHSA-f689-fh93-2pm2 github.com: https://github.com/exceljs/exceljs/blob/v4.4.0/lib/xlsx/xform/sheet/data-validations-xform.js#L216-L227 github.com: https://github.com/exceljs/exceljs/issues/3093 vulncheck.com: https://www.vulncheck.com/advisories/exceljs-through-4.4.0-denial-of-service-via-oversized-data-validation-sqref
Credits
Matéo Florian Callec