CVE-2026-20963
Microsoft SharePoint Remote Code Execution Vulnerability
Exploited in the wild. In CISA KEV since 2026‑03‑18. Fixed versions are out.
What to do
Find your product and version, then upgrade to the build on the right.
- Microsoft SharePoint Server Subscription EditionAffected: ≥ 16.0.0, < 16.0.19127.20442Upgrade to: 16.0.19127.20442Stated by: CVE record
- Microsoft SharePoint Server 2019Affected: ≥ 16.0.0, < 16.0.10417.20083Upgrade to: 16.0.10417.20083Stated by: CVE record
- Microsoft SharePoint Enterprise Server 2016Affected: ≥ 16.0.0, < 16.0.5535.1001Upgrade to: 16.0.5535.1001Stated by: CVE record
- Microsoft Sharepoint ServerAffected: < 16.0.19127.20442Upgrade to: 16.0.19127.20442Stated by: NVD
Versions as the sources state them. Full version matrix after sign-in
Coverage timeline
2 publishersMicrosoft disrupted a phishing infrastructure selling kits and compromised cloud accounts via an underground marketplace, having facilitated over one billion scam messages.
Added to CISA KEV catalog
Sourced from public security reporting — each date is when it was published, not when it happened.
What it is
From the CVE record
Deserialization of untrusted data in Microsoft Office SharePoint allows an authorized attacker to execute code over a network.
In plain language
No plain-language summary for this CVE yet.
Exploitation
Where each signal puts this CVE on the scale from published to confirmed exploited.
- CISA KEV
Listed as exploited in the wild since 2026-03-18.
US federal agencies must remediate by 2026-03-21.
Apply mitigations per vendor instructions, follow applicable BOD 22-01 guidance for cloud services, or discontinue use of the product if mitigations are unavailable.
- Public exploits
No public exploit or proof of concept found in the sources we track.
- EPSS
29% chance of exploitation activity in the next 30 days, which ranks it in the 98th percentile of scored CVEs.
Exploit Prediction Scoring System, FIRST.org. A probability, not a confirmation.
Lifecycle
8 events over 163 days, from the signal feeds we watch.
- OpenVAS check added
- EPSS band changelow → moderate
- Added to CISA KEV
- Patch availablerecord updated
- Publishedweakness classified, att&ck mapped
Affected products
And 3 more affected products. See all after sign-in
Technical detail
CVSS 3.1 vector
Open in the CVSS calculatorCVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H
Scored 8.8 by NVD.
How it is reached
- Attack Vector NetworkExploitable remotely over the network without any special conditions
- Attack Complexity LowNo special conditions — the attack can be reliably reproduced
- Privileges Required LowRequires basic user-level privileges
- User Interaction NoneNo user interaction needed — fully automated exploitation
Scope
- Scope UnchangedImpact is limited to the vulnerable component itself
Impact if exploited
- Confidentiality HighTotal information disclosure — all data in the component is compromised
- Integrity HighTotal loss of integrity — attacker can modify any data in the component
- Availability HighTotal denial of service — the component is completely unavailable
Weaknesses
ATT&CK techniques
Mapped from the weaknesses above (CWE to ATT&CK), not observed in attacks.
Sources
Watch the software you run.
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We'll flag the next CVE, public exploit or patch for Sharepoint Server, not every advisory. This one: actively exploited.
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