CVE-2026-45453Network attack vector

Spoofing via undisclosed cross-site scripting flaw

Published Jun 9, 2026 · Updated Jun 9, 2026

Cross-site scripting in Microsoft SharePoint Server allows remote attackers to spoof content through crafted web input. Microsoft has not disclosed the affected component or the input that is rendered without adequate neutralization. Successful exploitation requires user interaction and can expose or alter data presented in the affected browser session.

CVSS severity5.4
Medium
EPSS probability0.51%
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 Microsoft SharePoint Server allows remote attackers to spoof content through crafted web input. Microsoft has not disclosed the affected component or the input that is rendered without adequate neutralization. Successful exploitation requires user interaction and can expose or alter data presented in the affected browser session.

The record

CVE
CVE-2026-45453
Published
Jun 9, 2026
Updated
Jun 9, 2026
Vendor
Microsoft
Product
Microsoft SharePoint Enterprise Server 2016
Classifications
CWE-79
Attack vector
network
Privileges
unauthenticated

Timeline

How it unfolded

  1. Jun 9, 2026CVE publishedPublication date reported by the CVE source.
  2. Jun 9, 2026Record updatedLatest update available in the CVE record.

Exploitability

Present is not the same as exploitable

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Is a vulnerable build present?

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

  1. Affected versionversion=16.0.0 <16.0.5556.1005

What conditions does exploitation require?

Attack vectornetwork
Required privilegesunauthenticated

What is affected?

Microsoft · Microsoft SharePoint Enterprise Server 2016version=16.0.0 <16.0.5556.1005
Microsoft · Microsoft SharePoint Server 2019version=16.0.0 <16.0.10417.20153
Microsoft · Microsoft SharePoint Server Subscription Editionversion=16.0.0 <16.0.19725.20384

Published CVSS scores

5.4Microsoft CorporationCVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:L/I:L/A:N
5.4NIST NVDCVSS:3.1/AV:N/AC:L/PR:L/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 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

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Your stack

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