CVE-2026-128347 json
ExcelJS through 4.4.0 Arbitrary File Read via WorkbookWriter addImage Filename
published 29d ago modified 17h ago also EUVD-2026-125152 , GHSA-f9m8-8qmf-qq29
Unreviewed: the maintainers' own advisory
Published by the maintainers on their GitHub repository mateocallec/exceljs-hardened. GitHub has not reviewed it into the GitHub Advisory Database, so the affected packages and versions are the maintainers' word. Read the full advisory on GitHub.
- cvss
- 7.5
- version 3.1, CNA
- cisa kev
- Not listed
- not in CISA's catalog
- epss
- 0.6%
- EPSS 0.6% chance of exploitation in 30 days, percentile 46%
- public exploits
- 0
- none known
Summary
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.
Patch / fix
- npm exceljs-hardened 5.1.0
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- Exploitation
- none
- Automatable
- yes
- Technical impact
- partial
- Assessed
- yesterday
Exploit prediction
0.56% chance of exploitation in the next 30 days, higher than 46% of all scored CVEs (FIRST EPSS, 2026-11-14).
CVSS scores
| assigned by | version | score | vector |
|---|---|---|---|
| CNA | 4.0 | 8.7 | 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 |
| CNA | 3.1 | 7.5 | CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:N/A:N |
| CNA | 4.0 | 8.7 | 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 |
Affected packages
| ecosystem | package | affected | fixed in |
|---|---|---|---|
| npm | exceljs-hardened | <=5.0.2 |
5.1.0 |
Affected products
- exceljs exceljs
Classification
- Weakness
-
- CWE-73 External Control of File Name or Path
References
-
github.com
/exceljs/exceljs
product
-
github.com
/mateocallec/exceljs-hardened/security/advisories/GHSA-f9m8-8qmf-qq29
third-party-advisory, advisory
-
github.com
/exceljs/exceljs/blob/v4.4.0/lib/stream/xlsx/workbook-writer.js#L230-L237
technical-description
-
github.com
/exceljs/exceljs/blob/v4.4.0/lib/stream/xlsx/workbook-writer.js#L124-L130
technical-description
-
vulncheck.com
/advisories/exceljs-through-4.4.0-arbitrary-file-read-via-workbookwriter-addimage-filename
third-party-advisory
Sources
- CVE List CVE-2026-128347
- NVD CVE-2026-128347
- Maintainer advisory GHSA-f9m8-8qmf-qq29
Fencer Intel keeps one entry per vulnerability: the CVE id wins, then GHSA, and records that alias each other are merged, except that two CVEs always keep separate entries. The same data is available as JSON.
The maintainers of mateocallec/exceljs-hardened published their own advisory on GitHub. Reviewed sources take precedence over it.