CVE-2025-51966Public exploitNetwork attack vector

Privileged JavaScript execution via unsanitized PDF FontMatrix

Published Sep 2, 2025 · Updated Sep 2, 2025

Cross-site scripting in uTools 7.1.1 and earlier allows context-dependent attackers to execute JavaScript through a crafted PDF preview. The PDF.js renderer fails to sanitize executable content embedded in a font's FontMatrix field and evaluates it while loading font resources. Execution requires a user to save, find, and select the crafted PDF in the Windows file-search preview, exposing data and actions available to the application's privileged context.

CVSS severity6.1
Medium
EPSS probability0.25%
Next 30 days · Sep 16, 2026
Known exploitationUnconfirmed
Based on sourced intelligence
Hinoki checkNot available
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Summary

What happened

Cross-site scripting in uTools 7.1.1 and earlier allows context-dependent attackers to execute JavaScript through a crafted PDF preview. The PDF.js renderer fails to sanitize executable content embedded in a font's FontMatrix field and evaluates it while loading font resources. Execution requires a user to save, find, and select the crafted PDF in the Windows file-search preview, exposing data and actions available to the application's privileged context.

The record

CVE
CVE-2025-51966
Published
Sep 2, 2025
Updated
Sep 2, 2025
Vendor
Unknown vendor
Product
Unknown product
Classifications
CWE-79, T1204.002
Attack vector
network
Privileges
unauthenticated

Timeline

How it unfolded

  1. Sep 2, 2025CVE publishedPublication date reported by the CVE source.
  2. Sep 2, 2025Record updatedLatest update available in the CVE record.

Exploitability

Present is not the same as exploitable

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Is a vulnerable build present?

Affected buildAffected product and version details are unavailable.

What conditions does exploitation require?

Attack vectornetwork
Required privilegesunauthenticated

What is affected?

Affected products and versions are unavailable in this record.

Published CVSS scores

6.1CISA-ADPCVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:C/C:L/I:L/A:N

CVSS describes severity. EPSS estimates exploitation probability.

Attacks

What attackers are doing with it

Daily unique IPs observed by Shadowserver honeypots for known exploited vulnerabilities (KEVs). Missing observations do not establish an absence of attacks.

Daily unique IPsNo honeypot observations are available for this CVE in the selected window.

No observations available

Sep 10, 2026Sep 16, 2026
Latest reporting daySep 16, 2026
Latest daily unique IPsUnavailable
Prior 30-day averageUnavailable
SourceShadowserver honeypots (KEV)
Vectornetwork
Privilegesunauthenticated
Known exploitationUnconfirmed
Public exploitPublished

Weakness, pattern, technique

CWE-79Improper Neutralization of Input During Web Page Generation ('Cross-site Scripting')
T1204.002User Execution: Malicious File

Public exploit references

Labels summarize the accepted research assessment. They do not indicate a test against your environment.

Technologies

Your stack

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Your stack

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