CVE-2026-66808: Microsoft SharePoint Server Remote Code Execution Vulnerability

Q: What is the severity of CVE-2026-66808?

CVE-2026-66808 has a severity rating of 8.8, categorized as high.

Q: How do I fix CVE-2026-66808?

To fix CVE-2026-66808, apply the available patches from Microsoft for affected SharePoint versions.

Q: What types of software are affected by CVE-2026-66808?

CVE-2026-66808 affects Microsoft SharePoint Server, including Subscription Editions and SharePoint Enterprise Server 2016 and 2019.

Q: What kind of attack can be executed via CVE-2026-66808?

CVE-2026-66808 allows an authorized attacker to execute remote code over a network due to deserialization of untrusted data.

Q: When was CVE-2026-66808 published?

CVE-2026-66808 was published on August 11, 2026.

Published Aug 11, 2026

Updated

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

Other sources

Microsoft SharePoint Server Remote Code Execution Vulnerability

— Microsoft

Affected Software

6 affected componentsFixes available

Microsoft SharePoint Server Subscription Edition<16.0.19725.20522

16.0.19725.20522

Microsoft SharePoint Enterprise Server 2016<16.0.5565.1001

16.0.5565.1001

Microsoft SharePoint Server 2019<16.0.10417.20198

16.0.10417.20198

Microsoft SharePoint Server<16.0.19725.20522

Microsoft SharePoint Server=2016

Microsoft SharePoint Server=2019

Remediation

Patch Available

https://msrc.microsoft.com/update-guide/vulnerability/CVE-2026-66808

Event History

Aug 11, 2026

CVE Published

via Microsoft·02:00 PM

Data Sourced

via Microsoft·02:00 PM

DescriptionSeverityWeakness

Data Sourced

via Microsoft·02:00 PM

Affected Software

Updated

via Microsoft·02:00 PM

Affected Software

Updated

via Microsoft·02:00 PM

Description

CVE Published

via MITRE·05:07 PM

Data Sourced

via MITRE·05:07 PM

DescriptionSeverity

Data Sourced

via NVD·05:19 PM

RemedyDescriptionSeverityWeaknessAffected Software

Frequently Asked Questions

What is the severity of CVE-2026-66808?

CVE-2026-66808 has a severity rating of 8.8, categorized as high.

How do I fix CVE-2026-66808?

To fix CVE-2026-66808, apply the available patches from Microsoft for affected SharePoint versions.

What types of software are affected by CVE-2026-66808?

CVE-2026-66808 affects Microsoft SharePoint Server, including Subscription Editions and SharePoint Enterprise Server 2016 and 2019.

What kind of attack can be executed via CVE-2026-66808?

CVE-2026-66808 allows an authorized attacker to execute remote code over a network due to deserialization of untrusted data.

When was CVE-2026-66808 published?

CVE-2026-66808 was published on August 11, 2026.

CVE-2026-66808: Microsoft SharePoint Server Remote Code Execution Vulnerability

Other sources

Affected Software

Remediation

Patch Available

Event History

Don't miss critical vulnerabilities

Frequently Asked Questions

What is the severity of CVE-2026-66808?

How do I fix CVE-2026-66808?

What types of software are affected by CVE-2026-66808?

What kind of attack can be executed via CVE-2026-66808?

When was CVE-2026-66808 published?

Company

Resources

Contact

Frequently Asked Questions

What is the severity of CVE-2026-66808?

How do I fix CVE-2026-66808?

What types of software are affected by CVE-2026-66808?

What kind of attack can be executed via CVE-2026-66808?

When was CVE-2026-66808 published?