CVE Watch13 de nov. de 2026

CVE-2026-128337

ExcelJS through 4.4.0 contains a prototype pollution vulnerability in mergeConditionalFormattings that allows attackers to modify Object.pro

CVSS

7.0

Alta

EPSS

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KEV

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Exploit Today

0-100

Publicado: 13 de nov. de 2026 · Última mod.: 13 de nov. de 2026 · CWE-1321

EPSS · 30d

Ainda não há histórico EPSS suficiente.

Descrição técnica

ExcelJS through 4.4.0 contains a prototype pollution vulnerability in mergeConditionalFormattings that allows attackers to modify Object.prototype by supplying an x14:cfRule id of __proto__. Attackers can craft an xlsx file that, when loaded with xlsx.load(), sets properties such as type, direction, border and cfvo on every object in the process until it restarts.

Referências oficiais

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