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 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.

CVSS

No CVSS.

References

Link	Resource
https://github.com/mwilliamson/mammoth.js/commit/2888fa158d67c1419199f152326e12a05618b53e
https://github.com/mwilliamson/mammoth.js/commit/31f0c370be4b95ac4fa285fea3be970606735f16
https://raw.githubusercontent.com/mwilliamson/mammoth.js/master/NEWS
https://www.npmjs.com/package/mammoth

Configurations

No configuration.

History

24 Sep 2026, 04:18

Type	Values Removed	Values Added
New CVE

Information

Published : 2026-09-24 04:18

Updated : 2026-09-24 21:04

NVD link : CVE-2026-97151

Mitre link : CVE-2026-97151

CVE.ORG link : CVE-2026-97151

JSON object : View

Products Affected

No product.

CWE

CWE-1321

Improperly Controlled Modification of Object Prototype Attributes ('Prototype Pollution')

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