CVE-2021-40487

published 2021-10-13

CVE-2021-40487: Microsoft SharePoint Server Remote Code Execution Vulnerability

Priority P2 69 high 8.8 CVSS 3.1

AV N AC L PR L UI N S U C H I H A H

Microsoft SharePoint Server Remote Code Execution Vulnerability

Affected

9 ranges

Vendor	Product	Version range	Fixed in
microsoft	microsoft_sharepoint_enterprise_server_2016	>= 16.0.0 < 16.0.5227.1000	16.0.5227.1000
microsoft	microsoft_sharepoint_foundation_2013_service_pack_1	>= 15.0.0 < 15.0.5389.1000	15.0.5389.1000
microsoft	microsoft_sharepoint_server_2019	>= 16.0.0 < 16.0.10379.20000	16.0.10379.20000
microsoft	sharepoint_enterprise_server	—	—
microsoft	sharepoint_foundation	—	—
microsoft	sharepoint_server	—	—
msrc	microsoft_sharepoint_enterprise_server_2016	—	—
msrc	microsoft_sharepoint_foundation_2013_service_pack_1	—	—
msrc	microsoft_sharepoint_server_2019	—	—

Detection & IOCs extracted from sources · hover to see the quote

• → Exploitation requires an authenticated attacker who can create a site on the SharePoint Server — monitor for authenticated users creating new SharePoint sites followed by unusual process execution from SharePoint worker processes. ↗

• · Exploitation is rated 'More Likely' for both latest and older software releases of Microsoft SharePoint Server, indicating active exploitation risk across patched and unpatched versions until the fix is applied. ↗
• · The vulnerability is network-based and requires authentication; perimeter controls alone are insufficient — internal authenticated users are a threat vector. ↗

CVSS provenance

nvd v3.1 8.8 HIGH CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H

nvd v2.0 6.5 MEDIUM AV:N/AC:L/Au:S/C:P/I:P/A:P

vendor_msrc 8.1 HIGH

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CWE-94