CVE-2021-42294Network attack vector

Authenticated code execution via undisclosed network vector

Published Dec 15, 2021 · Updated Aug 4, 2024

Remote code execution in Microsoft SharePoint Server allows remote authenticated users to execute code through an undisclosed network vector. Microsoft has not published the affected component or the operation that mishandles attacker-controlled input. Exploitation requires high privileges and can compromise stored data or interrupt the SharePoint server.

CVSS severity7.2
High
EPSS probability2.18%
Next 30 days · Sep 16, 2026
Known exploitationUnconfirmed
Based on sourced intelligence
Hinoki checkNot available
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Summary

What happened

Remote code execution in Microsoft SharePoint Server allows remote authenticated users to execute code through an undisclosed network vector. Microsoft has not published the affected component or the operation that mishandles attacker-controlled input. Exploitation requires high privileges and can compromise stored data or interrupt the SharePoint server.

The record

CVE
CVE-2021-42294
Published
Dec 15, 2021
Updated
Aug 4, 2024
Vendor
Microsoft
Product
Microsoft SharePoint Foundation 2013
Classifications
T1190
Attack vector
network
Privileges
admin

Timeline

How it unfolded

  1. Dec 15, 2021CVE publishedPublication date reported by the CVE source.
  2. Aug 4, 2024Record 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 <15.0.5407.1000

What conditions does exploitation require?

Attack vectornetwork
Required privilegesadmin

What is affected?

Microsoft · Microsoft SharePoint Foundation 2013version=15.0.0 <15.0.5407.1000
Microsoft · Microsoft SharePoint Enterprise Server 2016version=16.0.0 <16.0.5254.1000
Microsoft · Microsoft SharePoint Enterprise Server 2013version=15.0.0 <15.0.5407.1000
Microsoft · Microsoft SharePoint Server 2019version=16.0.0 <16.0.10381.20001
Microsoft · Microsoft SharePoint Server Subscription Edition Language Packversion=16.0.0 <16.0.14326.20620
Microsoft · Microsoft SharePoint Server Subscription Editionversion=16.0.0 <16.0.14326.20620

Published CVSS scores

7.2Microsoft CorporationCVSS:3.1/AV:N/AC:L/PR:H/UI:N/S:U/C:H/I:H/A:H
6.5NIST NVDAV:N/AC:L/Au:S/C:P/I:P/A:P

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
Privilegesadmin
Known exploitationUnconfirmed
Public exploitUnconfirmed

Weakness, pattern, technique

T1190Exploit Public-Facing Application

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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