CVE-2021-34520

mediumpriority · track · 28EPSS 0.044 · 91 %ileEURUUS

grimoire priorityP3 · Track

Exploitable?

—

no known exploitation

Likely / severe?

4.42% (91st) EPSS

CVSS 6.5 · medium

Is it mine?

15 products

Check your exposure

Who says so?

5 sources

cnnvd · enisa_euvd · fstec_bdu · msrc_csaf

EPSS · scored 2026-10-27

Microsoft SharePoint Server Remote Code Execution Vulnerability

remediations

Vendor fix, mitigation, or workaround guidance, as published by each source.

A vendor fix is available.

FixedMicrosoft SharePoint Enterprise Server 2016msrc_csaf
16.0.5188.1000:Security Update:https://support.microsoft.com/kb/5001976
https://support.microsoft.com/kb/5001976
FixedMicrosoft SharePoint Foundation 2013 Service Pack 1msrc_csaf
15.0.5363.1000:Security Update:https://support.microsoft.com/kb/5001992
https://support.microsoft.com/kb/5001992
FixedMicrosoft SharePoint Server 2019msrc_csaf
16.0.10376.20001:Security Update:https://support.microsoft.com/kb/5001975
https://support.microsoft.com/kb/5001975

cvss

Technical severity, 0–10. One row per scoring source.

8.8

010

base score 0–10 · higher = more severe · hover a vector to decode⚠ sources disagree · medium–high · 5.5–8.8

v2.06.5mediumAV:N/AC:L/Au:S/C:P/I:P/A:Pprimary · NVD / NIST USexploitability 8 · impact 6.4

v2.05.5mediumAV:N/AC:L/Au:S/C:P/I:P/A:P/E:Usecondary · CVSS-BT (t0sche)

v3.18.8highAV:N/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:Hsecondary · FSTEC (BDU) RU

v3.18.1highCVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:Nsecondary · secure@microsoft.com USexploitability 2.8 · impact 5.2

v3.18.1highCVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:N/E:U/RL:O/RC:Csecondary · Microsoft Security Response Center US

v3.18.1highCVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:N/E:U/RL:O/RC:Csecondary · ENISA EU

v3.18.8highCVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:Hsecondary · NVD / NIST USexploitability 2.8 · impact 5.9

weaknesses

The CWE weakness classes this flaw belongs to.

CWE-502USprimaryCWE-502US

affected products (15)

Products and version ranges known to be affected.

Microsoft Microsoft SharePoint Enterprise Server 201616.0.0 → 16.0.5188.1000enisa_euvdEU
Microsoft Microsoft SharePoint Foundation 2013 Service Pack 115.0.0 → 15.0.5363.1000enisa_euvdEU
Microsoft Microsoft SharePoint Server 201916.0.0 → 16.0.10376.20001enisa_euvdEU
Microsoft Corp Microsoft SharePoint Enterprise Server 2016all versionsfstec_bduRU
Microsoft Corp Microsoft SharePoint Foundation≤ 2013 SP1fstec_bduRU
Microsoft Corp Microsoft SharePoint Server 2019all versionsfstec_bduRU
Microsoft SharePoint Enterprise Server 2016all versionsfixedmsrc_csafUS
Microsoft SharePoint Enterprise Server 2016< 16.0.5188.1000msrc_csafUS
Microsoft SharePoint Foundation 2013 Service Pack 1all versionsfixedmsrc_csafUS
Microsoft SharePoint Foundation 2013 Service Pack 1< 15.0.5363.1000msrc_csafUS
Microsoft SharePoint Server 2019all versionsfixedmsrc_csafUS
Microsoft SharePoint Server 2019< 16.0.10376.20001msrc_csafUS
microsoft sharepoint foundation= 2013nvdUScpe:2.3:a:microsoft:sharepoint_foundation:*:*:*:*:*:*:*:*
microsoft sharepoint server= 2016nvdUScpe:2.3:a:microsoft:sharepoint_server:*:*:*:*:*:*:*:*
microsoft sharepoint server= 2019nvdUScpe:2.3:a:microsoft:sharepoint_server:*:*:*:*:*:*:*:*

advisories (1)

Vendor and ecosystem advisories describing this.

msrc_CVE-2021-34520Microsoft SharePoint Server Remote Code Execution Vulnerability2021-07-13csaf · msrc_csafUS
To determine the support lifecycle for your software, see the Microsoft Support Lifecycle: https://support.microsoft.com/lifecycle

also known as (6)

Other names and identifiers for this entity.

sources

Which sources assert this record, and when.

cnnvd enisa_euvd fstec_bdu msrc_csaf nvd NVD CVE.org MITRE

published 2021-07-14modified 2026-08-10

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+3739 more

references (10)

External citations — patches, advisories, analysis.

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