Live › vulnerability › CVE-2026-55040
Go to dashboardMicrosoft SharePoint has a weak authentication flaw that lets an unauthenticated remote attacker bypass a security feature over the network. 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 | vendor | – | – |
| microsoft sharepoint server | vendor | < 16.0.19725.20434 | 16.0.19725.20434 |
| microsoft sharepoint server | vendor | = 2016 | – |
| microsoft sharepoint server | vendor | = 2019 | – |
Each row is the first time that source carried this signal. The analyst’s rows are its own findings.
Microsoft SharePoint contains a weak authentication vulnerability which allows an unauthorized attacker to bypass a security feature 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-2026-55040")
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