Vulnerability record
CVE-2026-128344
The short answer
CVE-2026-128344 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 0.63%.
What it is
ExcelJS through 4.4.0 contains a memory exhaustion vulnerability that allows attackers to crash applications by supplying a workbook with an unbounded image anchor column in the drawing part. Attackers can set an anchor column such as 300000000 in xl/drawings/drawing1.xml so reading getImages() anchor positions makes Worksheet.getColumn allocate millions of Column objects and abort with a heap out-of-memory error.
Weakness: CWE-770.
Severity
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
Exploited (CISA KEV)
Not listed
CISA lists confirmed exploitation only
EPSS, next 30 days
0.63%
Higher than 51% 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
- None
- Integrity impact
- None
- Availability impact
- High
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/doc/anchor.js#L40-L64
- github.com/exceljs/exceljs/blob/v4.4.0/lib/doc/worksheet.js#L243-L261
- github.com/mateocallec/exceljs-hardened/security/advisories/GHSA-cqmf-h7c5-g7xx
- www.vulncheck.com/advisories/exceljs-through-4.4.0-memory-exhaustion-via-oversized-image-anchor-column
- github.com/mateocallec/exceljs-hardened/security/advisories/GHSA-cqmf-h7c5-g7xx
Questions
Is CVE-2026-128344 being exploited?
It is not in CISA's Known Exploited Vulnerabilities catalog as of 2026-11-14. FIRST's EPSS estimates a 0.63% chance of exploitation in the next 30 days.
How do I fix CVE-2026-128344?
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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