Microsoft Office SharePoint
CVE-2026-66808 — Microsoft SharePoint Server Remote Code Execution Vulnerability
Executive Summary
Deserialization of untrusted data in Microsoft Office SharePoint allows an authorized attacker to execute code over a network.
Overview
8.8
CVSS HIGH
Important
MS Severity
Not Exploited
MS Exploit Status
Less Likely
MS Exploit Likelihood
CVSS Vector
CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H/E:U/RL:O/RC:C
ATTACK VECTOR
Network
ATTACK COMPLEXITY
Low
PRIVILEGES REQUIRED
Low
USER INTERACTION
None
SCOPE
Unchanged
CONFIDENTIALITY
High
INTEGRITY
High
AVAILABILITY
High
EXPLOIT CODE MATURITY
Unproven
REMEDIATION LEVEL
Official Fix
REPORT CONFIDENCE
Confirmed
Temporal Score: 7.7
EPSS Score
0.01579
probability of exploitation in the next 30 days
0.73321 percentile - updated 2026-08-14
View on FIRST.org
Affected Products
1 affected product
| Product | KB Article | Severity | Impact | Restart Required |
|---|---|---|---|---|
| Microsoft SharePoint Enterprise Server 2016 5002905 (Security Update) 5002906 (Security Update) Important Remote Code Execution Base: 8.8 Temporal: 7.7 Vector: CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H/E:U/RL:O/RC:C 16.0.5565.1001 Maybe None Microsoft SharePoint Server 2019 5002894 (Security Update) 5002896 (Security Update) Important Remote Code Execution Base: 8.8 Temporal: 7.7 Vector: CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H/E:U/RL:O/RC:C 16.0.10417.20198 Maybe None Microsoft SharePoint Server Subscription Edition | 5002893 (Security Update) |
Important | Remote Code Execution | Maybe |
Patches
1 patch
| Article | Type | Restart |
|---|---|---|
5002893 |
Security Update | Maybe |
Known Exploits
No known exploits have been linked for this CVE yet. When available, exploit references will be sourced from public repositories and may be unverified, incomplete, or non-functional. Always review code carefully before use in any environment.
Acknowledgments
Anonymous
References
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