CVE-2023-36891Network attack vector

Authenticated script execution via undisclosed input neutralization

Published Aug 8, 2023 · Updated Aug 10, 2026

Cross-site scripting in Microsoft SharePoint Server allows remote authenticated users to execute script through crafted web content. Microsoft identifies improper neutralization during web page generation but has not disclosed the affected input, endpoint, or rendering operation. A victim must open the crafted content; the resulting script runs in that user's SharePoint context and can act with that user's privileges.

CVSS severity8.0
High
EPSS probability1.98%
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 authenticated users to execute script through crafted web content. Microsoft identifies improper neutralization during web page generation but has not disclosed the affected input, endpoint, or rendering operation. A victim must open the crafted content; the resulting script runs in that user's SharePoint context and can act with that user's privileges.

The record

CVE
CVE-2023-36891
Published
Aug 8, 2023
Updated
Aug 10, 2026
Vendor
Microsoft
Product
Microsoft SharePoint Server 2019
Classifications
CWE-79, T1204.001
Attack vector
network
Privileges
authenticated

Timeline

How it unfolded

  1. Aug 8, 2023CVE publishedPublication date reported by the CVE source.
  2. Aug 10, 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 <16.0.10401.20025

What conditions does exploitation require?

Attack vectornetwork
Required privilegesauthenticated

What is affected?

Microsoft · Microsoft SharePoint Server 2019version=16.0.0 <16.0.10401.20025
Microsoft · Microsoft SharePoint Server Subscription Editionversion=16.0.0 <16.0.16130.20684

Published CVSS scores

8.0Microsoft CorporationCVSS:3.1/AV:N/AC:L/PR:L/UI:R/S:U/C:H/I:H/A:H

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
Privilegesauthenticated
Known exploitationUnconfirmed
Public exploitUnconfirmed

Weakness, pattern, technique

CWE-79Improper Neutralization of Input During Web Page Generation ('Cross-site Scripting')
T1204.001User Execution: Malicious Link

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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