Live › vulnerability › CVE-2026-58644
Go to dashboardMicrosoft SharePoint has a deserialization of untrusted data flaw that lets an unauthenticated attacker run code 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 | – |
Unknown from the sources.
Apply the mitigations and patch from Microsoft's advisory for CVE-2026-58644 as directed by CISA BOD 26-04; if no mitigation exists, discontinue use of the affected SharePoint product.
Each row is the first time that source carried this signal. The analyst’s rows are its own findings.
Microsoft SharePoint contains a deserialization of untrusted data vulnerability that allows an unauthorized attacker to execute code 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.
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