CVE WatchSep 24, 2026

CVE-2026-97151

mammoth (aka mammoth.js) before 1.12.2 is vulnerable to prototype pollution when reading the styles defined in a document. Converting a craf

CVSS

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No CVSS

EPSS

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KEV

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Exploit Today

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0-100

Published: Sep 24, 2026 · Last modified: Sep 24, 2026 · CWE-1321

EPSS · 30d

Not enough EPSS history yet.

Technical description

mammoth (aka mammoth.js) before 1.12.2 is vulnerable to prototype pollution when reading the styles defined in a document. Converting a crafted .docx file allows an attacker to add arbitrary properties to Object.prototype. In 1.11.0 through 1.12.1, applications that convert further documents in the same process and return the converted HTML can also disclose the contents of local server files (to the party supplying the documents) by setting externalFileAccess to true.

Official references

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