Remote Code Execution Vulnerability in Microsoft SharePoint
CVE-2026-20963

8.8HIGH

Key Information:

Vendor

Microsoft
Status
Microsoft Sharepoint Enterprise Server 2016
Microsoft Sharepoint Server 2019
Microsoft Sharepoint Server Subscription Edition
Vendor
CVE Published:
13 January 2026

Badges

📈 Score: 373👾 Exploit Exists🦅 CISA Reported

What is CVE-2026-20963?

CVE-2026-20963 is a remote code execution vulnerability found in Microsoft SharePoint, a web-based collaboration and document management platform widely utilized in corporate environments. This vulnerability arises from the deserialization of untrusted data, which enables an authenticated attacker to execute arbitrary code remotely over a network connection. The potential implications for organizations that utilize Microsoft SharePoint are significant, as an attacker could manipulate the application to perform unauthorized actions, gain elevated privileges, or gain access to sensitive data stored within the platform.

As SharePoint is integral for document sharing, project management, and team collaboration, the exploitation of this vulnerability could undermine the security of corporate data, disrupt business operations, and jeopardize regulatory compliance. This vulnerability encompasses not only the immediate risks associated with unauthorized code execution but also the cascading effects that could ensue from a breach, including reputational damage and financial losses.

Potential impact of CVE-2026-20963

  1. Unauthorized Access and Control: Successful exploitation allows attackers to execute code remotely, potentially leading to unauthorized access to sensitive information, which might result in data breaches and loss of confidential business insights.

  2. Operational Disruption: The ability for an attacker to execute arbitrary code in SharePoint can disrupt normal business operations, leading to downtime and impacting productivity as teams may lose access to critical documents and collaboration tools.

  3. Increased Vulnerability to Subsequent Attacks: By establishing a foothold through this vulnerability, attackers may exploit the initial compromised access to launch further attacks within the organization's infrastructure, increasing the overall security risk and possible spread of malware.

CISA has reported CVE-2026-20963

CISA provides regional cyber and physical services to support security and resilience across the United States. CISA monitor the most dangerious vulnerabilities and have identifed CVE-2026-20963 as being exploited but is not known by the CISA to be used in ransomware campaigns. This is subject to change at pace

The CISA's recommendation is: Apply mitigations per vendor instructions, follow applicable BOD 22-01 guidance for cloud services, or discontinue use of the product if mitigations are unavailable.

Human OS v1.0:
Ageing Is an Unpatched Zero-Day Vulnerability.

Remediate biological technical debt. Prime Ageing uses 95% high-purity SIRT6 activation to maintain genomic integrity and bolster systemic resilience.

Deploy the Patch

Affected Version(s)

Microsoft SharePoint Enterprise Server 2016 x64-based Systems 16.0.0 < 16.0.5535.1001

Microsoft SharePoint Server 2019 x64-based Systems 16.0.0 < 16.0.10417.20083

Microsoft SharePoint Server Subscription Edition x64-based Systems 16.0.0 < 16.0.19127.20442

References

https://msrc.microsoft.com/update-guide/vulnerability/CVE...
vendor-advisorypatch

EPSS Score

9% chance of being exploited in the next 30 days.

CVSS V3.1

Score:
8.8
Severity:
HIGH
Confidentiality:
High
Integrity:
High
Availability:
High
Attack Vector:
Network
Attack Complexity:
Low
Privileges Required:
Low
User Interaction:
None
Scope:
Unchanged

Timeline

  • 👾

    Exploit known to exist

  • 🦅

    CISA Reported

  • Vulnerability published

  • Vulnerability Reserved

JSON
.