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TI-2026-47444 Aliases CVE-2026-66805GHSA-w35v-hpfj-gw86

Microsoft SharePoint Server Remote Code Execution Vulnerability

Priority MEDIUM 44CWE-502Published · Updated

Key facts

Attack vector
Network
Privileges required
Low
User interaction
None
Attack complexity
Low
Impact type
Code execution
Confidentiality · integrity · availability
High · High · High
Fix status
Fixed

Attack profile from CVSS 3.1 · CNA. Fix status from CNA, Red Hat and Microsoft. Impact type from Microsoft.

Summary

Deserialization of untrusted data in Microsoft Office SharePoint allows an authorized attacker to execute code over a network.

Why it matters now

Exploitation None reported CISA SSVC · not in CISA KEV
EPSS 0.02044 81st percentileScored 2026-11-07
Fix Fixed Red Hat: 12 advisoriesMicrosoft: 5 updates

SSVC decision points

CISA ADP · SSVC 2.0.3

Exploitation
None
Automatable
No
Technical impact
Total

The decision (Track, Attend, Act) also depends on your mission and well-being impact; see CISA's SSVC guide.

Affected products

VendorProductAffected versionsFixed inStatusSource
MicrosoftMicrosoft SharePoint Server Subscription Edition16.0.0 to before 16.0.20326.2019016.0.20326.20190Patch availableCNA
  • Microsoft SharePoint Server Subscription Edition VendorMicrosoft Affected 16.0.0 to before 16.0.20326.20190 Fixed in 16.0.20326.20190 Patch available CNA

CPE configurations NVD · 3

CPEVersionsRoleVendor
cpe:2.3:a:microsoft:sharepoint_server:*:*:*:*:subscription:*:*:*before 16.0.19725.20522VulnerableMicrosoft
cpe:2.3:a:microsoft:sharepoint_server:2016:*:*:*:enterprise:*:*:*2016VulnerableMicrosoft
cpe:2.3:a:microsoft:sharepoint_server:2019:*:*:*:*:*:*:*2019VulnerableMicrosoft
  • cpe:2.3:a:microsoft:sharepoint_server:*:*:*:*:subscription:*:*:* Versions before 16.0.19725.20522 Vulnerable ·Microsoft
  • cpe:2.3:a:microsoft:sharepoint_server:2016:*:*:*:enterprise:*:*:* Versions 2016 Vulnerable ·Microsoft
  • cpe:2.3:a:microsoft:sharepoint_server:2019:*:*:*:*:*:*:* Versions 2019 Vulnerable ·Microsoft

Remediation

Red Hat 12 advisories

  • RHSA-2026:60391 Released 2026-08-26 · Red Hat rating Important
    Red Hat Advanced Cluster Management for Kubernetes v2.16.4 security update
    • Red Hat Advanced Cluster Management for Kubernetes 2.16 registry.redhat.io/rhacm2/acm-governance-policy-addon-controller-rhel9, registry.redhat.io/rhacm2/acm-grafana-rhel9, registry.redhat.io/rhacm2/acm-multicluster-observability-addon-rhel9 +19
  • RHSA-2026:60390 Released 2026-08-26 · Red Hat rating Important
    Red Hat Advanced Cluster Management for Kubernetes v2.13.11 security update
    • Red Hat Advanced Cluster Management for Kubernetes 2.13 registry.redhat.io/rhacm2/acm-governance-policy-addon-controller-rhel9, registry.redhat.io/rhacm2/acm-grafana-rhel9, registry.redhat.io/rhacm2/acm-multicluster-observability-addon-rhel9 +23
  • RHSA-2026:60388 Released 2026-08-26 · Red Hat rating Important
    Red Hat Advanced Cluster Management for Kubernetes v2.14.4 security update
    • Red Hat Advanced Cluster Management for Kubernetes 2.14 registry.redhat.io/rhacm2/acm-governance-policy-addon-controller-rhel9, registry.redhat.io/rhacm2/acm-grafana-rhel9, registry.redhat.io/rhacm2/acm-multicluster-observability-addon-rhel9 +26
Show 9 more Red Hat advisories
  • RHSA-2026:60387 Released 2026-08-26 · Red Hat rating Important
    Red Hat Advanced Cluster Management for Kubernetes v2.11.11 security update
    • Red Hat Advanced Cluster Management for Kubernetes 2.11 registry.redhat.io/rhacm2/acm-governance-policy-addon-controller-rhel9, registry.redhat.io/rhacm2/acm-must-gather-rhel9, registry.redhat.io/rhacm2/acm-prometheus-config-reloader-rhel9 +24
  • RHSA-2026:60386 Released 2026-08-26 · Red Hat rating Important
    Red Hat Advanced Cluster Management for Kubernetes v2.17.1 security update
    • Red Hat Advanced Cluster Management for Kubernetes 2.17 registry.redhat.io/rhacm2/acm-governance-policy-addon-controller-rhel9, registry.redhat.io/rhacm2/acm-grafana-rhel9, registry.redhat.io/rhacm2/acm-multicluster-observability-addon-rhel9 +31
  • RHSA-2026:59593 Released 2026-08-25 · Red Hat rating Important
    multicluster engine for Kubernetes v2.17.2 security update
    • multicluster engine for Kubernetes 2.17 registry.redhat.io/multicluster-engine/cluster-api-provider-kubevirt-rhel9, registry.redhat.io/multicluster-engine/cluster-curator-controller-rhel9, registry.redhat.io/multicluster-engine/cluster-image-set-controller-rhel9 +6
  • RHSA-2026:59579 Released 2026-08-25 · Red Hat rating Important
    multicluster engine for Kubernetes v2.6.14 security update
    • multicluster engine for Kubernetes 2.6 registry.redhat.io/multicluster-engine/addon-manager-rhel9, registry.redhat.io/multicluster-engine/cluster-curator-controller-rhel9, registry.redhat.io/multicluster-engine/cluster-image-set-controller-rhel9 +17
  • RHSA-2026:59559 Released 2026-08-25 · Red Hat rating Important
    multicluster engine for Kubernetes v2.9.7 security update
    • multicluster engine for Kubernetes 2.9 registry.redhat.io/multicluster-engine/addon-manager-rhel9, registry.redhat.io/multicluster-engine/cluster-curator-controller-rhel9, registry.redhat.io/multicluster-engine/cluster-image-set-controller-rhel9 +15
  • RHSA-2026:59558 Released 2026-08-25 · Red Hat rating Important
    multicluster engine for Kubernetes v2.8.10 security update
    • multicluster engine for Kubernetes 2.8 registry.redhat.io/multicluster-engine/addon-manager-rhel9, registry.redhat.io/multicluster-engine/backplane-rhel9-operator, registry.redhat.io/multicluster-engine/cluster-api-provider-agent-rhel9 +20
  • RHSA-2026:57194 Released 2026-08-19 · Red Hat rating Important
    multicluster engine for Kubernetes v2.11.5 security update
    • multicluster engine for Kubernetes 2.11 registry.redhat.io/multicluster-engine/addon-manager-rhel9, registry.redhat.io/multicluster-engine/backplane-rhel9-operator, registry.redhat.io/multicluster-engine/cluster-api-provider-kubevirt-rhel9 +11
  • RHSA-2026:54432 Released 2026-08-12 · Red Hat rating Important
    multicluster engine for Kubernetes v2.10.5 security update
    • multicluster engine for Kubernetes 2.10 registry.redhat.io/multicluster-engine/cluster-api-provider-kubevirt-rhel9, registry.redhat.io/multicluster-engine/clusterclaims-controller-rhel9, registry.redhat.io/multicluster-engine/console-mce-rhel9 +1
  • RHSA-2026:54427 Released 2026-08-12 · Red Hat rating Important
    Red Hat Advanced Cluster Management for Kubernetes v2.15.5 security update
    • Red Hat Advanced Cluster Management for Kubernetes 2.15 registry.redhat.io/rhacm2/acm-prometheus-config-reloader-rhel9, registry.redhat.io/rhacm2/acm-prometheus-rhel9, registry.redhat.io/rhacm2/console-rhel9 +9

Microsoft 5 updates

  • Security Update
    • Microsoft SharePoint Enterprise Server 2016 16.0.5565.1001
  • Security Update
    • Microsoft SharePoint Enterprise Server 2016 16.0.5565.1001
  • Security Update
    • Microsoft SharePoint Server 2019 16.0.10417.20198
Show 2 more Microsoft updates
  • Security Update
    • Microsoft SharePoint Server 2019 16.0.10417.20198
  • Security Update
    • Microsoft SharePoint Server Subscription Edition 16.0.19725.20522

Vendor assessments

Red Hat

Red Hat rating: Important. Red Hat's page for this CVE →

ProductStatusPlan or fix
Red Hat Advanced Cluster Management for Kubernetes 2.11Fixed RHSA-2026:60387
Red Hat Advanced Cluster Management for Kubernetes 2.13Fixed RHSA-2026:60390
Red Hat Advanced Cluster Management for Kubernetes 2.14Fixed RHSA-2026:60388
Red Hat Advanced Cluster Management for Kubernetes 2.15Fixed RHSA-2026:54427
Red Hat Advanced Cluster Management for Kubernetes 2.16Fixed RHSA-2026:60391
Red Hat Advanced Cluster Management for Kubernetes 2.17Fixed RHSA-2026:60386
multicluster engine for Kubernetes 2.10Fixed RHSA-2026:54432
multicluster engine for Kubernetes 2.11Fixed RHSA-2026:57194
multicluster engine for Kubernetes 2.17Fixed RHSA-2026:59593
multicluster engine for Kubernetes 2.6Fixed RHSA-2026:59579
multicluster engine for Kubernetes 2.8Fixed RHSA-2026:59558
multicluster engine for Kubernetes 2.9Fixed RHSA-2026:59559
Not affected: 12 products
  • Red Hat Advanced Cluster Management for Kubernetes 2.11
  • Red Hat Advanced Cluster Management for Kubernetes 2.13
  • Red Hat Advanced Cluster Management for Kubernetes 2.14
  • Red Hat Advanced Cluster Management for Kubernetes 2.15
  • Red Hat Advanced Cluster Management for Kubernetes 2.16
  • Red Hat Advanced Cluster Management for Kubernetes 2.17
  • multicluster engine for Kubernetes 2.10
  • multicluster engine for Kubernetes 2.11
  • multicluster engine for Kubernetes 2.17
  • multicluster engine for Kubernetes 2.6
  • multicluster engine for Kubernetes 2.8
  • multicluster engine for Kubernetes 2.9

Microsoft

Microsoft's page for this CVE →

Impact
Remote Code Execution
Exploited
No
Publicly disclosed
No
Exploitability
Exploitation Less Likely

Timeline

  1. 2026-10-02 Threatist record created from CVE-2026-66805
  2. 2026-10-03 Alias added: GHSA-w35v-hpfj-gw86
  3. 2026-10-21 Fix available: Microsoft/Microsoft SharePoint Server Subscription [email protected] · CNA

References

  • TI-2026-42212 Microsoft SharePoint Remote Code Execution Vulnerability KEVCVSS 3.1CRITICAL 9.8
  • TI-2026-37256 Microsoft SharePoint Remote Code Execution Vulnerability KEVCVSS 3.1CRITICAL 9.8
  • TI-2026-16982 Microsoft SharePoint Remote Code Execution Vulnerability KEVCVSS 3.1CRITICAL 9.8
  • TI-2025-33671 Microsoft SharePoint Server Remote Code Execution Vulnerability KEVCVSS 3.1CRITICAL 9.8
  • TI-2023-13749 Microsoft SharePoint Server Elevation of Privilege Vulnerability KEVCVSS 3.1CRITICAL 9.8
  • TI-2019-00394 Improper input validation in Microsoft SharePoint Server KEVCVSS 3.1CRITICAL 9.8
See all 631 →

Sources