8.1High
Microsoft Sharepoint Foundation
CVE-2021-34520
Microsoft SharePoint Server Remote Code Execution Vulnerability
What this means for your business
- It affects Microsoft Sharepoint Foundation. It matters if your company, or a supplier that handles your data, runs it.
- An attacker can use it remotely, over a network, with an ordinary user login, and without anyone at your company clicking anything.
- FIRST's prediction model gives it a 4% chance of attack attempts being seen in the next 30 days, ranking above 90% of all known flaws.
What to do
- 1Check whether your company or your suppliers run Microsoft Sharepoint Foundation, and which version. The affected versions are listed further down this page.
- 2If you do, apply the vendor's fix. A patch or vendor advisory has been published.
Not sure if your company is exposed?
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Scoring
- CVSS
- 8.1 (v3.1)
- Vector
CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:N- Weakness
- CWE-502
- Assigned by
- secure@microsoft.com
Dates
- Published
- 2021-07-14
- Last modified
- 2026-08-10
- Sources
- NVD
Affected products
- Microsoft Sharepoint Foundation2013
- Microsoft Sharepoint Server2016, 2019
As listed in the NVD configuration data. Not a statement about your estate.