CVE-2026-97151

HIGH
8.4
CVSS Score
Published: September 24, 2026 at 03:08 AM UTC
Updated: September 24, 2026 at 09:17 PM UTC
1 product affected across 1 vendorMammoth.js

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Severity
HIGH8.4
Exploit prediction
EPSS 0.4%
SSVC
No known exploit

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.

Affected

Our own answer: ranges merged, affected separated from platform-only, with confidence and review flags.

v < 1.12.2
Affected range stops below 1.12.2, so it looks safe — our inference, not a vendor statement

SSVC — Action Prioritization

SSVCNo known exploitNot automatablePartial impact

SSVC signals action urgency (what to patch first), separate from CVSS which measures severity.

CVSS

8.4HIGHmitre
Vector?

Quick Info

StatusAWAITING ANALYSIS
CWE
CWE-1321

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