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CVE-2026-128346

7.5, high

ExcelJS through 4.4.0 contains a resource leak vulnerability in the streaming WorkbookReader.parse that leaves temporary files and open…

NVD (opens in a new tab) CVE.org (opens in a new tab)
CVSS
7.5, high high CVSS v3.1
EPSS, next 30 days
0.6% higher than 50.7% of scored CVEs
Exploitation
No public evidence
Published
13 Nov 2026yesterday

Description

ExcelJS through 4.4.0 contains a resource leak vulnerability in the streaming WorkbookReader.parse that leaves temporary files and open descriptors when sheet parsing fails or iteration stops early. Attackers can repeatedly upload malformed multi-sheet workbooks with worksheets placed before xl/sharedStrings.xml to fill the temporary directory and exhaust file descriptors.

Details

Vendor
Exceljs
Product
exceljs
Weakness
CWE-459 (opens in a new tab)
Status
Awaiting analysis
Updated
13 Nov 2026
Assigner
disclosure@vulncheck.com

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

References 5

Advisories 1

Other references 4

The kind is read from NVD's tags where present and from the shape of the URL otherwise, so treat it as a hint.

Other Exceljs CVEs

Every Exceljs CVE we hold

Same vendor in what we hold, not a known link between the flaws.

  • CVE-2026-128337 exceljs Prototype Pollution Vulnerability EPSS 0.4% 7, high
  • CVE-2026-128338 exceljs Allocation of Resources Without Limits or Throttling Vulnerability EPSS 0.6% 7.5, high
  • CVE-2026-128341 exceljs Allocation of Resources Without Limits or Throttling Vulnerability EPSS 0.6% 7.5, high
  • CVE-2026-128342 ExcelJS through 4.4.0 contains a denial of service vulnerability that allows attackers to block the event loop by supplying an unbounded… EPSS 0.6% 7.5, high

Beyond this page

Is CVE-2026-128346 in your network?

This page tells you how dangerous CVE-2026-128346 is out there. Whether it sits on one of your devices, only a scan of your own network can tell. That is what our systems do, every day, for the companies we protect.

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  • EXYS7950 KONDRA

    Detect it if it's exploited

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Check your exposure

Assembled from the NVD 2.0 API, the CISA Known Exploited Vulnerabilities Catalog and FIRST EPSS. Scores are as of our last collection on 14 Nov 2026, not the live upstream state.