# CVE-2026-73088: Browserslist: Uncaught crash / prototype write via untrusted browserslist-stats.json custom stats (normalizeStats)

> CVE-2026-73088: Browserslist: Uncaught crash / prototype write via untrusted browserslist-stats.json custom stats (normalizeStats). CVSS 7.5 (CVSS 3.1).

Canonical: https://rewindex.com/cve/CVE-2026-73088
Last updated: 2026-09-09T20:44:04Z

- Published: 2026-08-11 17:00 UTC · Updated: 2026-09-09 20:44 UTC · Assigner: GitHub\_M
- CVSS: 7.5 (CVSS 3.1) · Severity: High · Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H
- EPSS: 0.66%, 51th percentile (scored 2026-10-25)
- CISA KEV: no
- CWE: CWE-1321, CWE-248

## Description

Browserslist is a configuration tool for sharing target browsers and Node.js versions between front-end tools. Prior to 4.28.7, normalizeStats() in node.js, reached unconditionally through getStat() and loadStat() on every browserslist() call, processes untrusted browserslist-stats.json, opts.stats, and CLI --stats data with an unguarded for...in loop and plain-object bracket access and assignment, allowing inherited Object.prototype keys including \_\_proto\_\_, toString, valueOf, constructor, hasOwnProperty, and isPrototypeOf to cause an uncaught TypeError or modify the prototype of the returned normalized object. This issue is fixed in version 4.28.7.

## Affected vendors and products

- browserslist: browserslist

## Tracked companies

- [Jira](https://rewindex.com/company/jira.md)

## References

- [CVE record on cve.org](https://www.cve.org/CVERecord?id=CVE-2026-73088)
- [NVD entry](https://nvd.nist.gov/vuln/detail/CVE-2026-73088)
- [https://github.com/browserslist/browserslist/commit/f9914ad9effc865ccc27d816255625890b31ca51](https://github.com/browserslist/browserslist/commit/f9914ad9effc865ccc27d816255625890b31ca51)
- [https://github.com/browserslist/browserslist/releases/tag/4.28.7](https://github.com/browserslist/browserslist/releases/tag/4.28.7)
- [https://github.com/browserslist/browserslist/security/advisories/GHSA-73wf-gq98-2v4g](https://github.com/browserslist/browserslist/security/advisories/GHSA-73wf-gq98-2v4g)

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_Sources: CVE records from the CVE Program (cve.org). CVE® is a registered trademark of The MITRE Corporation. (https://www.cve.org/) This product uses data from the NVD API but is not endorsed or certified by the NVD. (https://nvd.nist.gov/) Known Exploited Vulnerabilities catalog from CISA. (https://www.cisa.gov/known-exploited-vulnerabilities-catalog) EPSS scores from FIRST (Exploit Prediction Scoring System). (https://www.first.org/epss/)_


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Canonical: https://rewindex.com/cve/CVE-2026-73088 · Markdown: https://rewindex.com/cve/CVE-2026-73088.md · JSON: https://rewindex.com/api/v1/cves/CVE-2026-73088 · Data licensed CC BY 4.0 (https://creativecommons.org/licenses/by/4.0/) · Generated 2026-10-26T03:10:41.591Z