CVE-2026-66808
HIGHCVSS 8.8/10
Last modified
CVE-2026-66808 is a high-severity vulnerability rated 8.8/10 on the CVSS scale. Deserialization of untrusted data in Microsoft Office SharePoint allows an authorized attacker to execute code over a network..
Description
Deserialization of untrusted data in Microsoft Office SharePoint allows an authorized attacker to execute code over a network.
Metrics
CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H
Weakness Enumeration
Affected Software
Source: CNA advisory (CVE.org). NVD analysis pending.
| Vendor | Product | Versions |
|---|---|---|
| Microsoft | Microsoft SharePoint Enterprise Server 2016 | >= 16.0.0, < 16.0.5565.1001 |
| Microsoft | Microsoft SharePoint Server 2019 | >= 16.0.0, < 16.0.10417.20198 |
| Microsoft | Microsoft SharePoint Server Subscription Edition | >= 16.0.0, < 16.0.19725.20522 |
References
Timeline
- Published
- Last Modified
- Status
- Undergoing Analysis
Frequently Asked Questions
What is CVE-2026-66808?
Deserialization of untrusted data in Microsoft Office SharePoint allows an authorized attacker to execute code over a network.
How severe is CVE-2026-66808?
CVE-2026-66808 has a CVSS score of 8.8/10 (HIGH severity).
How do I fix CVE-2026-66808?
Check the vendor references and advisories linked above for patched versions and mitigation guidance. You can also run a Strix scan to test if your systems are affected.
How Strix Helps
- How Strix found a critical auth bypass in etcdStrix autonomously discovered a critical authentication bypass in etcd, later designated CVE-2026-33413.
- Autonomous PentestingAI agents that find and validate exploitable vulnerabilities like this one across your applications.
- PR ReviewsPentest every pull request so vulnerable code is caught before it ships to production.
- AI Penetration TestingHow AI-driven penetration testing continuously covers your attack surface.
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Are you affected by CVE-2026-66808?
Run a free Strix scan to check your systems for this vulnerability.
Scan your code nowSource: NVD / NIST