Vulnerability record
CVE-2026-128347
The short answer
CVE-2026-128347 affects exceljs exceljs and is rated high (CVSS 8.7). It is not in CISA's KEV catalog; EPSS puts the chance of exploitation in the next 30 days at 0.51%.
What it is
ExcelJS through 4.4.0 contains an arbitrary file read vulnerability in the streaming WorkbookWriter that allows attackers to read local files by supplying crafted image filenames to addImage. Attackers can inject ../ path segments into user-controlled image paths, causing addMedia to embed any file readable by the Node.js process under xl/media in the generated workbook.
Weakness: CWE-73.
Severity
8.7 high
CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:H/VI:N/VA:N/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
Exploited (CISA KEV)
Not listed
CISA lists confirmed exploitation only
EPSS, next 30 days
0.51%
Higher than 44% of scored CVEs
How it can be exploited
- Attack vector
- Network
- Attack complexity
- Low
- Attack requirements
- None
- Privileges required
- None
- User interaction
- None
- Confidentiality impact
- High
- Integrity impact
- None
- Availability impact
- None
Affected products
exceljs. NVD's record lists the exact affected versions.
References
- github.com/exceljs/exceljs
- github.com/exceljs/exceljs/blob/v4.4.0/lib/stream/xlsx/workbook-writer.js#L124-L130
- github.com/exceljs/exceljs/blob/v4.4.0/lib/stream/xlsx/workbook-writer.js#L230-L237
- github.com/mateocallec/exceljs-hardened/security/advisories/GHSA-f9m8-8qmf-qq29
- www.vulncheck.com/advisories/exceljs-through-4.4.0-arbitrary-file-read-via-workbookwriter-addimage-filename
Questions
Is CVE-2026-128347 being exploited?
It is not in CISA's Known Exploited Vulnerabilities catalog as of 2026-11-13. FIRST's EPSS estimates a 0.51% chance of exploitation in the next 30 days.
How do I fix CVE-2026-128347?
Follow the vendor advisory in the references below. NVD lists the affected versions under its configurations.
From NVD, CISA KEV, FIRST EPSS and OSV.dev, checked . Status on NVD: Awaiting Analysis. The description is NVD's text, quoted as published.
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