CVE-2026-56164

Microsoft SharePoint Server Elevation of Privilege Vulnerability

Missing authentication for critical function in Microsoft Office SharePoint allows an unauthorized attacker to elevate privileges over a network.

Affected

Microsoft · Microsoft SharePoint Enterprise Server 2016 · Microsoft SharePoint Server 2019 · Microsoft SharePoint Server Subscription Edition

CVSS v3.1 NVD

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

CVSS v3.1 MICROSOFT

5.3 MEDIUMCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:L/A:N

EPSS

1.01% chance of exploitation in the next 30 days, 63rd percentile

CISA KEV

added 2026-07-14

Published

2026-07-14

Updated

2026-10-08

Proof-of-concept exploits (2)

• sentinel-aidefense/CVE-2026-56164-EXP12★ · 2026-07-15
• sam00/POC-CVE-2026-56164-exploit2★ · 2026-08-06

Security advisories

• https://msrc.microsoft.com/update-guide/vulnerability/CVE-2026-56164

References

• CVE Record
• NVD entry

Related

• CVE-2026-0163
• CVE-2026-54998
• CVE-2026-69836
• CVE-2026-0300
• CVE-2026-32621
• CVE-2026-42826