# exceljs (npm) vulnerabilities

5 known vulnerabilities (1 critical, 3 high), with the versions each affects and the releases that fix them.

## At a glance

- Latest release: 4.4.0 (Oct 19, 2023): affected by 4 advisories
- Newest unaffected release: Every release is affected by at least one advisory
- Weekly downloads: 26.2M
- Dependents: 5,009
- Releases: 166 since 0.0.1 (Dec 9, 2014)
- Registry: https://www.npmjs.com/package/exceljs
- Releases read: Nov 8, 2026

## Version timeline

Affected versions per advisory, in version order:

- CVE-2026-78209: 0.0.1 to 4.4.0 (4.4.1-prerelease.0 is outside it)
- CVE-2026-78208: 0.0.1 to 4.4.0 (4.4.1-prerelease.0 is outside it)
- CVE-2026-78207: 0.0.1 to 4.4.0 (4.4.1-prerelease.0 is outside it)
- CVE-2026-78206: 0.0.1 to 4.4.0 (4.4.1-prerelease.0 is outside it)
- CVE-2018-16459: 0.0.1 to 1.5.1 (1.6.0 is outside it)

## Advisories (5)

### [CVE-2026-78209](https://cve.now/CVE-2026-78209): exceljs through 4.4.0 CSV Formula Injection via Unescaped Cell Values

- Severity: High 8.4
- Published: Aug 24, 2026
- Affected: through 4.4.0.
- No fix released. The latest release, 4.4.0, is still affected.
- 99.8% of exceljs downloads last week were affected versions (28.2M).

### [CVE-2026-78208](https://cve.now/CVE-2026-78208): exceljs through 4.4.0 Path Traversal via Unvalidated addImage filename

- Severity: High 8.7
- Published: Aug 24, 2026
- Affected: through 4.4.0.
- No fix released. The latest release, 4.4.0, is still affected.
- 99.8% of exceljs downloads last week were affected versions (28.2M).

### [CVE-2026-78207](https://cve.now/CVE-2026-78207): exceljs through 4.4.0 Prototype Pollution via deepMerge Reached From Note Serialization

- Severity: Critical 9.3
- Published: Aug 24, 2026
- Affected: through 4.4.0.
- No fix released. The latest release, 4.4.0, is still affected.
- 99.8% of exceljs downloads last week were affected versions (28.2M).

### [CVE-2026-78206](https://cve.now/CVE-2026-78206): exceljs through 4.4.0 Uncontrolled Resource Consumption via Unbounded xlsx Decompression

- Severity: High 8.7
- Published: Aug 24, 2026
- Affected: through 4.4.0.
- No fix released. The latest release, 4.4.0, is still affected.
- 99.8% of exceljs downloads last week were affected versions (28.2M).

### [CVE-2018-16459](https://cve.now/CVE-2018-16459): An unescaped payload in exceljs \<v1.6 allows a possible XSS via cell value when worksheet is displayed in browser.

- Severity: Unrated
- Published: Sep 6, 2018
- Affected: fixed in 1.6.0.
- Fixed in 1.6.0 (released Aug 2, 2018, 35 days before disclosure).
- The latest release, 4.4.0, is not affected.
- <0.1% of exceljs downloads last week were affected versions (8.5K).

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