CVE-2026-97151 (GCVE-0-2026-97151)

Vulnerability from cvelistv5 – Published: 2026-09-24 03:08 – Updated: 2026-09-24 03:08
VLAI
Summary
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.
Severity
8.4 (High)
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
CWE
  • CWE-1321 - Improperly Controlled Modification of Object Prototype Attributes ('Prototype Pollution')
Assigner
References
Impacted products
Vendor Product Version CPE status
mwilliamson mammoth.js Affected: 0 , < 1.12.2 (semver)
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{
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          "modules": [
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          "packageURL": "pkg:npm/mammoth",
          "product": "mammoth.js",
          "programFiles": [
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          "programRoutines": [
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          "vendor": "mwilliamson",
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        }
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            "Recovery": "NOT_DEFINED",
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              "description": "CWE-1321 Improperly Controlled Modification of Object Prototype Attributes (\u0027Prototype Pollution\u0027)",
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          "url": "https://www.npmjs.com/package/mammoth"
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          "url": "https://github.com/mwilliamson/mammoth.js/commit/31f0c370be4b95ac4fa285fea3be970606735f16"
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          "supportingMedia": [
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              "type": "text/html",
              "value": "Upgrade to mammoth 1.12.2 or later.\u003cbr\u003e"
            }
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    "cveId": "CVE-2026-97151",
    "datePublished": "2026-09-24T03:08:15.523Z",
    "dateReserved": "2026-09-24T03:08:15.164Z",
    "dateUpdated": "2026-09-24T03:08:15.523Z",
    "state": "PUBLISHED"
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          }
        ],
        "id": "CVE-2026-97151",
        "lastModified": "2026-09-24T04:18:06.027",
        "metrics": {
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                "Recovery": "NOT_DEFINED",
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                "exploitMaturity": "NOT_DEFINED",
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                "modifiedAttackComplexity": "NOT_DEFINED",
                "modifiedAttackRequirements": "NOT_DEFINED",
                "modifiedAttackVector": "NOT_DEFINED",
                "modifiedPrivilegesRequired": "NOT_DEFINED",
                "modifiedSubAvailabilityImpact": "NOT_DEFINED",
                "modifiedSubConfidentialityImpact": "NOT_DEFINED",
                "modifiedSubIntegrityImpact": "NOT_DEFINED",
                "modifiedUserInteraction": "NOT_DEFINED",
                "modifiedVulnAvailabilityImpact": "NOT_DEFINED",
                "modifiedVulnConfidentialityImpact": "NOT_DEFINED",
                "modifiedVulnIntegrityImpact": "NOT_DEFINED",
                "privilegesRequired": "NONE",
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                "valueDensity": "NOT_DEFINED",
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            "source": "cve@mitre.org",
            "type": "Primary"
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    }
  }
}



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Forecast uses a logistic model when the trend is rising, or an exponential decay model when the trend is falling. Fitted via linearized least squares.

Sightings

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Nomenclature

  • Seen: The vulnerability was mentioned, discussed, or observed by the user.
  • Confirmed: The vulnerability has been validated from an analyst's perspective.
  • Published Proof of Concept: A public proof of concept is available for this vulnerability.
  • Exploited: The vulnerability was observed as exploited by the user who reported the sighting.
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  • Not confirmed: The user expressed doubt about the validity of the vulnerability.
  • Not patched: The vulnerability was not observed as successfully patched by the user who reported the sighting.



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Vulnerabilities whose description is nearest to this one in the vector space of the CIRCL/vulnerability-attack-technique-biencoder model. This is a similarity search over the bi-encoder space (plain cosine), not a classification, and it has no measured accuracy.