CVE-2021-24104

Spoofing through an undisclosed mechanism

Published Mar 11, 2021 · Updated Aug 19, 2026

Spoofing in Microsoft SharePoint Foundation 2013, Server 2016, and Server 2019 allows attackers unspecified impact via unspecified vectors. Microsoft has not published the affected component, untrusted input, or incorrect operation that produces the spoofed result. The Microsoft assessment places the attacker locally with administrator-level privileges before the undisclosed condition is reachable.

CVSS severity4.6
Medium
EPSS probability1.37%
Next 30 days · Sep 16, 2026
Known exploitationUnconfirmed
Based on sourced intelligence
Hinoki checkNot available
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Summary

What happened

Spoofing in Microsoft SharePoint Foundation 2013, Server 2016, and Server 2019 allows attackers unspecified impact via unspecified vectors. Microsoft has not published the affected component, untrusted input, or incorrect operation that produces the spoofed result. The Microsoft assessment places the attacker locally with administrator-level privileges before the undisclosed condition is reachable.

The record

CVE
CVE-2021-24104
Published
Mar 11, 2021
Updated
Aug 19, 2026
Vendor
Microsoft
Product
Microsoft SharePoint Foundation 2013
Classifications
Unavailable
Attack vector
local
Privileges
admin

Timeline

How it unfolded

  1. Mar 11, 2021CVE publishedPublication date reported by the CVE source.
  2. Aug 19, 2026Record 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=15.0.0 <15.0.5327.1000

What conditions does exploitation require?

Attack vectorlocal
Required privilegesadmin

What is affected?

Microsoft · Microsoft SharePoint Foundation 2013version=15.0.0 <15.0.5327.1000
Microsoft · Microsoft SharePoint Enterprise Server 2016version=16.0.0 <16.0.5134.1000
Microsoft · Microsoft SharePoint Server 2019version=16.0.0 <16.0.10372.20000

Published CVSS scores

5.8NIST NVDAV:N/AC:M/Au:N/C:P/I:P/A:N
5.4NIST NVDCVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:L/I:L/A:N
4.6Microsoft CorporationCVSS:3.1/AV:L/AC:L/PR:H/UI:N/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)
Vectorlocal
Privilegesadmin
Known exploitationUnconfirmed
Public exploitUnconfirmed

Weakness, pattern, technique

No sourced classifications are available.

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

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