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Critical

Microsoft SharePoint Deserialization of Untrusted Data Vulnerability

Type: advisorySource: CISA Known Exploited VulnerabilitiesKnown exploited1 source record

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.

Announced Source revision 1
Original source ↗

CVE-2026-58644

Primary source · Revision 1

Imported from structured advisory data. Source references identify upstream records or fields; verify affected versions and your deployed configuration.

Security context

Source reference: kev:CVE-2026-58644

SharePoint

Source reference: /product

Affected versions
Not stated in this record
Fixed versions
Not stated in this record
Prerequisites
Not stated in this record
Related CVEs
CVE-2026-58644

Source reference: /cveID

Publisher severity

No explicit severity was provided.

Linked CVE context

These ratings describe the referenced vulnerabilities and products. They are not a severity rating for every application using this dependency.

CVE-2026-58644 · Critical

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

Event
#110 · Revision 1
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Publisher date
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