CVE-2026-65660: Microsoft SharePoint Code Injection Vulnerability
- Is it exploited?
Yes. CISA added it to the Known Exploited Vulnerabilities catalog on , 45 days after the CVE record was published.
- How likely is exploitation in the next 30 days?
- 8.2%
EPSS score, percentile 94.8 of all scored records
- How severe?
- 8.8 High
CVSS v3.1 base score, given by the CNA
- What should I do?
CISA deadline . Apply mitigations in accordance with vendor instructions … Full text
- Which versions are affected?
Affected
- from 16.0.0 to before 16.0.5565.1001
- from 16.0.0 to before 16.0.10417.20198
- from 16.0.0 to before 16.0.19725.20522
Source: CISA Known Exploited Vulnerabilities (KEV) catalog, 2026.10.28, as of ; FIRST Exploit Prediction Scoring System (EPSS), v2026.06.15, as of ; CVE List V5 (CVE Program), cve_2026-10-28_0000Z, as of . About the data.
What to do
Required action, set by CISA
Apply mitigations in accordance with vendor instructions, ensuring compliance with CISA’s BOD 26-04 Prioritizing Security Updates Based on Risk (see URL in Notes) guidance and CISA’s “Forensics Triage Requirements” (see URL in Notes). Follow applicable BOD 26-04 guidance for cloud services or discontinue use of the product if mitigations are unavailable. Stakeholders are responsible for evaluating each asset's internet exposure and ensuring adherence to BOD 26-04 patching guidelines.
CISA due date for this action: .
Advisories and patches
Linked from CISA's catalog entry
- https://msrc.microsoft.com/update-guide/vulnerability/CVE-2026-65660
- https://www.cisa.gov/news-events/directives/bod-26-04-prioritizing-security-updates-based-risk
- https://www.cisa.gov/news-events/directives/bod-26-04-implementation-guidance-prioritizing-security-updates-based-risk
- https://nvd.nist.gov/vuln/detail/CVE-2026-65660
Affected products and versions
As listed in the CVE record.
| Status | Versions |
|---|---|
| Affected | from 16.0.0 to before 16.0.5565.1001 |
| Status | Versions |
|---|---|
| Affected | from 16.0.0 to before 16.0.10417.20198 |
| Status | Versions |
|---|---|
| Affected | from 16.0.0 to before 16.0.19725.20522 |
Source: CVE List V5 (CVE Program), cve_2026-10-28_0000Z, as of . About the data.
About this vulnerability
Microsoft SharePoint contains a code injection vulnerability which could allow an authorized attacker to execute code over a network.
Summary: CISA's KEV catalog, as of .
- CISA added CVE-2026-65660 to its Known Exploited Vulnerabilities (KEV) catalog on 25 Sep 2026.
- CISA's ransomware flag for this entry is "Unknown": no evidence of ransomware use in the catalog, which is not proof of none.
- The due date CISA sets for the required action is 28 Sep 2026.
- The CVE record was published on 11 Aug 2026, 45 days before it was added to KEV.
- The CVE record carries a CVSS v3.1 base score of 8.8 (High), given by its CNA.
- FIRST's EPSS model puts the probability of exploitation in the next 30 days at 8.2% (percentile 94.8), as of 28 Oct 2026.
- CISA's SSVC assessment in the CVE record: exploitation active, automatable no, technical impact total.
Source: CISA Known Exploited Vulnerabilities (KEV) catalog, 2026.10.28, as of ; CVE List V5 (CVE Program), cve_2026-10-28_0000Z, as of ; FIRST Exploit Prediction Scoring System (EPSS), v2026.06.15, as of . About the data.
Description
Microsoft SharePoint Server Remote Code Execution Vulnerability
Improper control of generation of code ('code injection') in Microsoft Office SharePoint allows an authorized attacker to execute code over a network.
Source: CVE List V5 (CVE Program), cve_2026-10-28_0000Z, as of . About the data.
Weakness
- CWE-94: Improper Control of Generation of Code ('Code Injection')
CWE and CAPEC are maintained by MITRE; the entries are those named in the CVE record and the KEV entry.
Timeline
| Date | Event |
|---|---|
| CVE record published | |
| Added to CISA KEV | |
| CISA due date for the required action | |
| CVE record last updated |
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