CVE-2025-64677Network attack vector

Unauthenticated content spoofing via undisclosed cross-site scripting

Published Dec 18, 2025 · Updated Dec 18, 2025

Cross-site scripting in Microsoft Office Out-of-Box Experience allows remote attackers to spoof setup content over a network. Microsoft has not published the affected input, rendering locus, or unsafe operation that fails to neutralize the input before web page generation. No authentication or user interaction is required, but the public record establishes spoofed setup content rather than code execution or service interruption.

CVSS severity8.2
High
EPSS probability0.52%
Next 30 days · Sep 16, 2026
Known exploitationUnconfirmed
Based on sourced intelligence
Hinoki checkNot available
Coverage for this vulnerability

See if you're affected

Explore vulnerability checks for your environment with Hinoki.

Book a demo

Summary

What happened

Cross-site scripting in Microsoft Office Out-of-Box Experience allows remote attackers to spoof setup content over a network. Microsoft has not published the affected input, rendering locus, or unsafe operation that fails to neutralize the input before web page generation. No authentication or user interaction is required, but the public record establishes spoofed setup content rather than code execution or service interruption.

The record

CVE
CVE-2025-64677
Published
Dec 18, 2025
Updated
Dec 18, 2025
Vendor
Microsoft
Product
Office Out-of-Box Experience
Classifications
CWE-79
Attack vector
network
Privileges
unauthenticated

Timeline

How it unfolded

  1. Dec 18, 2025CVE publishedPublication date reported by the CVE source.
  2. Dec 18, 2025Record updatedLatest update available in the CVE record.

Exploitability

Present is not the same as exploitable

Compare your product and version with the public record. A matching version still requires validation against your environment.

Is a vulnerable build present?

Compare these published version ranges with your installed build and any vendor patches.

  1. Affected versionversion=N/A

What conditions does exploitation require?

Attack vectornetwork
Required privilegesunauthenticated

What is affected?

Microsoft · Office Out-of-Box Experienceversion=N/A

Published CVSS scores

8.2NIST National Vulnerability DatabaseCVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:C/C:H/I:L/A:N
8.2Microsoft CorporationCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/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 exploitUnconfirmed

Weakness, pattern, technique

CWE-79Improper Neutralization of Input During Web Page Generation ('Cross-site Scripting')

Public exploit references

No public exploit references are available in this record.

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

Technologies

Your stack

See the directory against your own environment.

Your stack

Check the software in your environment

Book a demo to see how Hinoki identifies affected software and validates exploitability in your environment.

Book a demo