CVE-2026-40365

HIGH

Published May 12, 2026 Modified May 13, 2026 CWE-1220

Description

Insufficient granularity of access control in Microsoft Office SharePoint allows an authorized attacker to execute code over a network.

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CVSS v3.1 Score

8.8

HIGH

CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H

EPSS — Exploit Prediction

0.0010

Probability of exploitation

0.27%

Percentile rank

EPSS estimates the probability that this vulnerability will be exploited in the wild within the next 30 days. A higher score means more likely to be exploited.

Weakness Type (CWE)

CWE-1220 CWE-1220

Affected Products

Vendor	Product	Versions
microsoft	sharepoint_server	< 16.0.19725.20280
microsoft	sharepoint_server	All
microsoft	sharepoint_server	All

References

Advisories & Patches

https://msrc.microsoft.com/update-guide/vulnerability/CVE-2026-40365

Frequently Asked Questions

What is CVE-2026-40365? +

Insufficient granularity of access control in Microsoft Office SharePoint allows an authorized attacker to execute code over a network. It has a CVSS v3.1 base score of 8.8 (HIGH).

How severe is CVE-2026-40365? +

CVE-2026-40365 has a CVSS v3.1 score of 8.8 out of 10, rated HIGH. This is a high-severity vulnerability that should be prioritized for patching. The EPSS score is 0.0010, placing it in the 0th percentile for exploitation probability.

What products are affected by CVE-2026-40365? +

CVE-2026-40365 affects products from microsoft, specifically: sharepoint_server. Check the affected products table above for specific version ranges.

How do I check if I'm vulnerable to CVE-2026-40365? +

You can use Secably's free Website Scanner to check your website for known vulnerabilities. For infrastructure scanning, use the Port Scanner to identify exposed services that may be affected. Check the vendor advisories linked above for specific patch and version information.