CVE-2026-66805
CVSS v3
8.8
HIGH
EPSS Score
1.6 %
exploit probability
CISA KEV
No
known exploited
Exploitation
—
SSVC status
Description
Deserialization of untrusted data in Microsoft Office SharePoint allows an authorized attacker to execute code over a network.
Technical details
- CVSS v3 Vector
- 3.1
- Published
- 2026-08-11
- Last Modified
- 2026-08-12
Frequently asked questions
What is CVE-2026-66805?
Deserialization of untrusted data in Microsoft Office SharePoint allows an authorized attacker to execute code over a network.
Is CVE-2026-66805 actively exploited?
Active exploitation of CVE-2026-66805 has not been confirmed. The EPSS score is 1.6%, indicating the estimated probability of exploitation in the next 30 days.
What is the CVSS score for CVE-2026-66805?
CVE-2026-66805 has a CVSS v3 base score of 8.8 (HIGH severity), with vector string 3.1.
Is CVE-2026-66805 affecting your environment?
Use isMalicious to check if any of your IPs or domains are associated with this vulnerability's IOCs.
No credit card required · 500 free checks/month · Free API key
Other 2026 vulnerabilities worth triaging
Ranked by exploit probability (EPSS).
- CVE-2026-24061KEV
- CVE-2026-27174MajorDoMo Unauthenticated Remote Code Execution via Admin Console Eval
- CVE-2026-60004KEV
- CVE-2026-1281KEV
- CVE-2026-24423KEVSmarterTools SmarterMail < Build 9511 Unauthenticated RCE via ConnectToHub API
- CVE-2026-1731KEVRemote code execution vulnerability in BeyondTrust Remote Support (RS) and Privileged Remote Access (PRA)
- CVE-2026-23760KEVSmarterTools SmarterMail < Build 9511 Authentication Bypass via Password Reset API
- CVE-2026-22200osTicket (1.18.x < 1.18.3, 1.17.x < 1.17.7) PDF Export Arbitrary File Read