CVE-2026-65660 — Sharepoint Server
HIGHCVE-2026-65660 is a high-severity (CVSS 8.8) Code Injection vulnerability in microsoft sharepoint server. A fix is available — see the affected versions and patch details below.
Improper control of generation of code ('code injection') in Microsoft Office SharePoint allows an authorized attacker to execute code over a network.
Exploitation Status
Actively exploited in the wild
- CISA’s SSVC triage classifies this CVE as under active exploitation.
- A successful exploit gives an attacker total control of the affected component, not partial access.
Exploitation and automatability from CISA’s SSVC triage for CVE-2026-65660.
EPSS Exploitation Probability
Probability of exploitation in the next 30 days, from FIRST.org EPSS.
How urgent is this, really
CVE-2026-65660 by exploitation likelihood (EPSS) against impact (CVSS). Outside the shaded patch-first corner.
Where this sits among everything scored
Of 385,738 CVEs with a current EPSS score, this one falls in the < 10% band (highlighted). Counts from FIRST.org, log-scaled.
Description
Improper control of generation of code ('code injection') in Microsoft Office SharePoint allows an authorized attacker to execute code over a network.
Affected Products
sharepoint servermicrosoftDetection & mitigation playbook
Vendor / applianceDetect
Inventory every microsoft sharepoint server deployment and check each version against the affected-products list above.
Fix
Apply the microsoft sharepoint server security patch or hotfix for CVE-2026-65660 on the affected version, following the vendor advisory for your exact build.
Workarounds
Stop passing untrusted input into the interpreter or shell: call the affected binary with an argument array rather than a composed command string, reject anything outside a strict allowlist of expected values, and run the component under an account that cannot reach beyond the work it legitimately does. Alongside that, restrict the management interface to trusted networks and apply the vendor's recommended configuration mitigations.
Frequently Asked Questions
Is CVE-2026-65660 being exploited in your environment?
Detect and block the exploit chain at execution, on systems you cannot patch yet.