9.8
Critical
Exploited
CVE-2026-20963 Microsoft SharePoint Deserialization of Untrusted Data Vulnerability
Active exploitation observed
· CISA KEV catalogue
Required action
Apply mitigations per vendor instructions, follow applicable BOD 22-01 guidance for cloud services, or discontinue use of the product if mitigations are unavailable.
Ransomware campaigns
Not observed so far
Weakness
CWE-502
Description
Deserialization of untrusted data in Microsoft Office SharePoint allows an unauthorized attacker to execute code over a network.
Affected products and versions
| Product | Affected versions | Fixed in |
|---|---|---|
| Microsoft SharePoint Enterprise Server 2016 16.0 | 16.0.0 → < 16.0.5535.1001 | 16.0.5535.1001 |
| Microsoft SharePoint Server 2019 16.0 | 16.0.0 → < 16.0.10417.20083 | 16.0.10417.20083 |
| Microsoft SharePoint Server Subscription Edition 16.0 | 16.0.0 → < 16.0.19127.20442 | 16.0.19127.20442 |
References
- Microsoft SharePoint Remote Code Execution Vulnerability msrc.microsoft.com
Timeline
- Published
- Added to the KEV catalogue
- Last modified
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