ChangeIntel IT change radar

Public mode

No access to your tenant or devices. Every item links to its source. What this means

CVE-2026-97151

mammoth.js · Vulnerability

CVSS 4.0 8.4 HIGHCheck source for fixed versionsKEV status unknown

Original advisory

Historical advisory recorded 23 Oct 2026 15:48:27 UTC. Read the latest advisory.

cve-program · CVE-2026-97151

Published

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.

Read the publisher's advisory

Affected versions, risk and source history

cve-program · CVE-2026-97151

Published

mammoth

https://registry.npmjs.org

Publisher's version information

Shown as published. These rules are not interpreted as NuGet package version ranges.

{
                    "collectionURL": "https://registry.npmjs.org",
                    "defaultStatus": "unaffected",
                    "modules": [
                        "docx styles reader"
                    ],
                    "packageName": "mammoth",
                    "packageURL": "pkg:npm/mammoth",
                    "product": "mammoth.js",
                    "programFiles": [
                        "lib/docx/styles-reader.js"
                    ],
                    "programRoutines": [
                        {
                            "name": "readStylesXml"
                        }
                    ],
                    "repo": "https://github.com/mwilliamson/mammoth.js",
                    "vendor": "mwilliamson",
                    "versions": [
                        {
                            "lessThan": "1.12.2",
                            "status": "affected",
                            "version": "0",
                            "versionType": "semver"
                        }
                    ]
                }

Original source record · Cite this exact observation · Complete original publisher JSON