Live › vulnerability › CVE-2026-56164
Go to dashboardMicrosoft SharePoint Server has a missing authentication check on a critical function that lets an unauthenticated network attacker gain elevated privileges. CISA lists it as actively exploited in the wild.
Summary written from the sources below. Check the originals before acting.
First seen by InfraStack 2026-10-23 19:11 UTC, 5h before NVD. All times on this page are UTC.
Apply mitigations in accordance with vendor instructions, ensuring compliance with CISA’s BOD 26-04 Prioritizing Security Updates Based on Risk (see URL in Notes) guidance and CISA’s “Forensics Triage Requirements” (see URL in Notes). Follow applicable BOD 26-04 guidance for cloud services or discontinue use of the product if mitigations are unavailable. Stakeholders are responsible for evaluating each asset's internet exposure and ensuring adherence to BOD 26-04 patching guidelines.
| Product | Ecosystem | Affected | Fixed in |
|---|---|---|---|
| microsoft sharepoint server | vendor | < 16.0.19725.20434 | 16.0.19725.20434 |
| microsoft sharepoint server | vendor | = 2016 | – |
| microsoft sharepoint server | vendor | = 2019 | – |
| Microsoft SharePoint Server | vendor | – | – |
Unknown from the sources.
Apply the Microsoft security update or mitigations for CVE-2026-56164 per vendor instructions and CISA BOD 26-04; if no mitigation exists, discontinue use of the product as CISA directs.
Each row is the first time that source carried this signal. The analyst’s rows are its own findings.
Microsoft SharePoint contains a missing authentication for critical function vulnerability that allows an unauthorized attacker to elevate privileges over a network.
CISA required action: Apply mitigations in accordance with vendor instructions, ensuring compliance with CISA’s BOD 26-04 Prioritizing Security Updates Based on Risk (see URL in Notes) guidance and CISA’s “Forensics Triage Requirements” (see URL in Notes). Follow applicable BOD 26-04 guidance for cloud services or discontinue use of the product if mitigations are unavailable. Stakeholders are responsible for evaluating each asset's internet exposure and ensuring adherence to BOD 26-04 patching guidelines.
This page as .md · .json · in your agent: get_signal("CVE-2026-56164")
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