CVE-2026-45659Microsoft SharePoint Remote Code Execution Vulnerability
Updated under an hour ago ()
Does this affect you?
It affects Microsoft SharePoint Enterprise Server 2016 and 3 other products. Add what you run to find out whether that includes you.
CISA lists it as known exploited since Jul 1, 2026; federal agencies had to remediate by Jul 4, 2026, and it is known to be used in ransomware. Treat that date as your deadline.
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Deserialization of untrusted data in Microsoft Office SharePoint allows an authorized attacker to execute code over a network.
- CVSS
- 8.8 HIGH (v3.1, CNA)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
- Weakness (CWE)
- CWE-502
- Known exploited
- Added to CISA KEV Jul 1, 2026; federal remediation due Jul 4, 2026; known ransomware useApply 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.
- EPSS (exploitation in the next 30 days)
- 2.70% (percentile 86)
- Assigned by
- microsoft
- NVD analysis
- Analyzed
- Record last updated
- Aug 11, 2026
- First seen by InfoSec Signals
- Oct 9, 2026
Affected products
Microsoft Microsoft SharePoint Enterprise Server 2016 microsoft:sharepoint_enterprise_server_2016 (from the name) | from 16.0.0 before 16.0.5552.1002 | CNA record |
Microsoft Microsoft SharePoint Server 2019 microsoft:sharepoint_server_2019 (from the name) | from 16.0.0 before 16.0.10417.20128 | CNA record |
Microsoft Microsoft SharePoint Server Subscription Edition microsoft:sharepoint_server_subscription_edition (from the name) | from 16.0.0 before 16.0.19725.20280 | CNA record |
microsoft sharepoint_server microsoft:sharepoint_server | before 16.0.19725.20280; 2016; 2019 | NVD |
References
- https://msrc.microsoft.com/update-guide/vulnerability/CVE-2026-45659vendor-advisory, patch
- https://www.cisa.gov/known-exploited-vulnerabilities-catalog?field_cve=CVE-2026-45659us-government-resource
The CVE record on cve.org NVD's entry
The CVE record is authoritative. Products marked “from the name” were identified from the CNA's free-text names, not a CPE, and are matched less certainly. This product uses the NVD API but is not endorsed or certified by the NVD.