CVE-2026-97151

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.

Overview

State: PUBLISHED
Assigner (CNA): mitre
CVSS severity: HIGH
CVSS score: 8.4 / 10
CVSS vector: CVSS:4.0/AV:N/AC:L/AT:P/PR:N/UI:N/VC:H/VI:L/VA:H/SC:N/SI:N/SA:N
Effective score: 8.4 / 10 HIGH source: CNA overview
CWE(s): CWE-1321
Reserved: 2026-09-24
Published: 2026-09-24 03:08 UTC
Last updated: 2026-09-24 13:02 UTC
Source: https://raw.githubusercontent.com/CVEProject/cvelistV5/main/cves/2026/97xxx/CVE-2026-97151.json
Linked Threat: CVE-2026-97151 — CVE-2026-97151

NVD triage scoring NVD CVE 2.0

Layer NVD adds on top of the CNA's CVE record — published / last-modified timestamps, exploitability / impact subscores, and the FIRST.org EPSS probability that this CVE will be exploited in the wild in the next 30 days.

NVD published: 2026-09-24 04:18:06 UTC
NVD last modified: 2026-09-24 21:04:40 UTC
EPSS score: 0.0036 (probability of exploitation in next 30 days)
EPSS percentile: 26.52% vs all CVEs — higher = more likely to be exploited, as of 2026-09-24

European Union Vulnerability Database ENISA EUVD

ENISA's official EU repository for curated vulnerability intelligence. Carries a separate identifier (EUVD-YYYY-NNNN) and frequently exposes an earlier-published description + CVSS than NVD does.

EUVD ID: EUVD-2026-85782
Assigner: mitre
Published: Sep 24, 2026, 3:08:15 AM
Updated: Sep 24, 2026, 1:02:42 PM
EUVD base score (CVSS 4.0): 8.4 / 10
CVSS:4.0/AV:N/AC:L/AT:P/PR:N/UI:N/VC:H/VI:L/VA:H/SC:N/SI:N/SA:N
EUVD-reported EPSS: 0.3600
Vendors: mwilliamson
Products: mammoth.js (0 <1.12.2)
Aliases: GHSA-89qm-22qm-xf5h

ENISA 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.

EUVD references (4)

Affected products (1)

Vendor	Product	Versions	Platforms
mwilliamson	mammoth.js	`0` (affected)	—

Vendor references (4)

References embedded in the original CVE record by the assigning CNA.

https://raw.githubusercontent.com/mwilliamson/mammoth.js/master/NEWS release-notesvendor-advisory
https://www.npmjs.com/package/mammoth product
https://github.com/mwilliamson/mammoth.js/commit/31f0c370be4b95ac4fa285fea3be970606735f16 patch
https://github.com/mwilliamson/mammoth.js/commit/2888fa158d67c1419199f152326e12a05618b53e patch

Web references (0)

DuckDuckGo results ranked by threat-intel / vendor advisory domains. Generated by the 🔎 Find references (web) button above — same flow as the Remediations search.

No web references attached yet.

NVD-tagged references (4)

Reference list NVD curates from the CNA record, vendor advisories, and third-party reports. The tag chips below are NVD's analyst-assigned categories.

https://github.com/mwilliamson/mammoth.js/commit/2888fa158d67c1419199f152326e12a05618b53e cve@mitre.org
https://github.com/mwilliamson/mammoth.js/commit/31f0c370be4b95ac4fa285fea3be970606735f16 cve@mitre.org
https://raw.githubusercontent.com/mwilliamson/mammoth.js/master/NEWS cve@mitre.org
https://www.npmjs.com/package/mammoth cve@mitre.org

Remediations (10)

Remediations are stored against the linked Threat row; the list below is deduplicated across both pages.

July 2026 Critical Patch Update Released | security - Oracle Blogs

web:blogs.oracle.com

For more information about the Critical Patch Update program, see the security vulnerability remediation practices page located on the Oracle Trust Center.

2026-09-25 10:08 UTC
CVE-2026-97151: Mammoth Js Prototype Pollution | CVETodo

web:cvetodo.com

CVE-2026-97151 is a CVSS 8.4 Prototype Pollution vulnerability in Mwilliamson Mammoth Js. Includes technical details, affected versions, and mitigation steps.

2026-09-25 10:08 UTC
CVE-2026-97151: Product identification pending

web:itknowledgebases.com

Export to CSV for reporting, ticketing, or patch prioritization workflows. What Is a CVE Advisory? A CVE (Common Vulnerabilities and Exposures) advisory is a public disclosure of a security vulnerability assigned a unique identifier by MITRE. Advisories include severity scores (CVSS), affected versions, and remediation guidance.

2026-09-25 10:08 UTC
Cisco Advance Notification for Publication of September 16, 2026 ...

web:sec.cloudapps.cisco.com

On September 16, 2026 , the Cisco Product Security Incident Response Team (PSIRT) published the advisories that are listed in the following tables. To remediate these vulnerabilities, Cisco strongly recommends that customers upgrade to the fixed software that is indicated in the advisories. For more information about changes in Cisco PSIRT vulnerability disclosure, see Strengthening the ...

2026-09-25 10:08 UTC
July 2026 Critical Patch Update Fixes 1,400+ Oracle Flaws

web:thecyberexpress.com

Oracle's July 2026 Critical Patch Update fixes 1,449 security flaws across 334 products, including 600 remotely exploitable vulnerabilities.

2026-09-25 10:08 UTC
What Is CVE Remediation in 2026? - aikido.dev

web:www.aikido.dev

CVE remediation is fixing known flaws in the software you run. Why upgrading often fails, what remediation actually involves, and how backporting fixes it.

2026-09-25 10:08 UTC
CVE: Common Vulnerabilities and Exposures

web:www.cve.org

At cve .org, we provide the authoritative reference method for publicly known information-security vulnerabilities and exposures

2026-09-25 10:08 UTC
National Vulnerability Database | NIST

web:www.nist.gov

NIST maintains the National Vulnerability Database (NVD), a repository of information on software and hardware flaws that can compromise computer security. This is a key piece of the nation's cybersecurity infrastructure.

2026-09-25 10:08 UTC
Oracle Critical Patch Update Advisory - January 2026

web:www.oracle.com

Oracle Critical Patch Update Advisory - January 2026 Description A Critical Patch Update is a collection of patches for multiple security vulnerabilities. These patches address vulnerabilities in Oracle code and in third party components included in Oracle products. These patches are usually cumulative, but each advisory describes only the security patches added since the previous Critical ...

2026-09-25 10:08 UTC
Oracle Critical Patch Update Advisory - July 2026

web:www.oracle.com

This Critical Patch Update contains 1448 new security patches across the product families listed below. Please note that a My Oracle Support (MOS) note summarizing the content of this Critical Patch Update and other Oracle Software Security Assurance activities is located at July 2026 Critical Patch Update: Executive Summary and Analysis.

2026-09-25 10:08 UTC

AI Forensic Analysis

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Raw JSON

The full cvelistV5 record. Download as CVE-2026-97151.json.

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