CVE-2026-63520

highpriority · track · 10EPSS 0.010 · 61 %ileexploit · PoCDEEUNLRUUS

grimoire priorityP1 · Urgent

Exploitable?

Public exploit

1 exploit · PoC

Likely / severe?

0.96% (61st) EPSS

CVSS 8.1 · high

Is it mine?

73 products

Check your exposure

Who says so?

6 sources

cnnvd · enisa_euvd · fstec_bdu · cert_bund

EPSS · scored 2026-10-27

Improper input validation in Microsoft Office SharePoint allows an unauthorized attacker to execute code over a network.

remediations

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

A vendor fix is available.

FixedMicrosoft SharePoint Enterprise Server 2016msrc_csaf
16.0.5565.1001:Security Update:https://support.microsoft.com/help/5002905
https://support.microsoft.com/help/5002905
FixedMicrosoft SharePoint Server 2019msrc_csaf
16.0.10417.20198:Security Update:https://support.microsoft.com/help/5002894
https://support.microsoft.com/help/5002894
FixedMicrosoft SharePoint Server Subscription Editionmsrc_csaf
16.0.19725.20522:Security Update:https://support.microsoft.com/help/5002893
https://support.microsoft.com/help/5002893

cvss

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

8.1

010

base score 0–10 · higher = more severe · hover a vector to decode

v3.18.1highAV:N/AC:H/PR:N/UI:N/S:U/C:H/I:H/A:Hsecondary · FSTEC (BDU) RU

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

v3.18.1highCVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:H/A:Hsecondary · secure@microsoft.com USexploitability 2.2 · impact 5.9

v3.18.1highCVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:H/A:H/E:Hsecondary · CVSS-BT (t0sche)

v3.18.1highCVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:H/A:Hsecondary · NCSC-NL NL

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

ssvc

A stakeholder decision — act, attend, or track — from exploitation and impact.

Exploitation: none · Automatable: no · Technical Impact: totalcoordinatorcisa_ssvcUS

weaknesses

The CWE weakness classes this flaw belongs to.

CWE-20USCWE-20USCWE-20US

exploits (1)

Public proof-of-concept and weaponised exploit code.

hypnguyen1209/CVE-2026-63520POC pre-auth RCE on Sharepoint chainPoC · poc_in_github

affected products (73)

Products and version ranges known to be affected.

Microsoft 365 Appsall versionscert_bundDEcpe:/a:microsoft:365_apps:-
Microsoft Access 2016all versionscert_bundDEcpe:/a:microsoft:access:2016
Microsoft Azure SQL Managed Instanceall versionscert_bundDEcpe:/a:microsoft:azure:sql_managed_instance
Microsoft Excel 2016all versionscert_bundDEcpe:/a:microsoft:excel:2016
Microsoft Office 2016all versionscert_bundDEcpe:/a:microsoft:office:2016
Microsoft Office 2019all versionscert_bundDEcpe:/a:microsoft:office:2019
Microsoft Office 365 for Macall versionscert_bundDEcpe:/a:microsoft:office_365:for_mac
Microsoft Office LTSC 2021all versionscert_bundDEcpe:/a:microsoft:office:ltsc_2021
Microsoft Office LTSC 2024all versionscert_bundDEcpe:/a:microsoft:office:ltsc_2024
Microsoft Office LTSC for Mac 2021all versionscert_bundDEcpe:/a:microsoft:office:ltsc_for_mac_2021
Microsoft Office LTSC for Mac 2024all versionscert_bundDEcpe:/a:microsoft:office:ltsc_for_mac_2024
Microsoft OneDrive for Androidall versionscert_bundDEcpe:/a:microsoft:onedrive:for_android
Microsoft Outlook 2016all versionscert_bundDEcpe:/a:microsoft:outlook:2016
Microsoft PowerPoint 2016all versionscert_bundDEcpe:/a:microsoft:powerpoint:2016
Microsoft Service Bus Azure Service Busall versionscert_bundDEcpe:/a:microsoft:service_bus:azure_service_bus
Microsoft SharePoint Enterprise Server 2016all versionscert_bundDEcpe:/a:microsoft:sharepoint:enterprise_server_2016
Microsoft SharePoint Onlineall versionscert_bundDEcpe:/a:microsoft:sharepoint:online
Microsoft SharePoint Server 2019all versionscert_bundDEcpe:/a:microsoft:sharepoint_server_2019:-
Microsoft SharePoint Server Subscription Editionall versionscert_bundDEcpe:/a:microsoft:sharepoint:server_subscription_edition
Microsoft Teamsall versionscert_bundDEcpe:/a:microsoft:teams:-

showing 20 of 73

advisories (3)

Vendor and ecosystem advisories describing this.

NCSC-2026-0286Kwetsbaarheden verholpen in Microsoft OfficeNL2026-08-11csaf · ncsc_nlNL
Microsoft heeft kwetsbaarheden verholpen in diverse Office producten.
WID-SEC-W-2026-2762Microsoft Office Produkte: Mehrere SchwachstellenDeutsch2026-08-11csaf · cert_bundDE
Ein Angreifer kann mehrere Schwachstellen in Microsoft Office Produkte ausnutzen, um Dateien zu manipulieren, um seine Privilegien zu erhöhen, um Informationen offenzulegen, um einen Cross-Site Scripting Angriff durchzuführen, und um beliebigen Programmcode auszuführen.
msrc_CVE-2026-63520Microsoft SharePoint Server Remote Code Execution Vulnerability2026-08-11csaf · msrc_csafUS
To determine the support lifecycle for your software, see the Microsoft Support Lifecycle: https://support.microsoft.com/lifecycle

also known as (4)

Other names and identifiers for this entity.

sources

Which sources assert this record, and when.

cnnvd enisa_euvd fstec_bdu cert_bund ncsc_nl msrc_csaf NVD CVE.org MITRE

published 2026-08-11modified 2026-09-04

references (3)

External citations — patches, advisories, analysis.

scry

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