CVE-2026-45659
CVE-2026-45659
Microsoft SharePoint Server Deserialization of Untrusted Data Vulnerability
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.
CVSS 3.1 · CNA · microsoft.com
chance of exploitation in the next 30 days (EPSS; in the top 1% of all CVEs)
Deserialization of untrusted data in Microsoft Office SharePoint allows an authorized attacker to execute code over a network.
Scores
Affected products
- microsoft sharepoint server: < 16.0.19725.20280; 2016; 2019
Weakness: CWE-502
2 references (advisories, patches, write-ups)
- https://msrc.microsoft.com/update-guide/vulnerability/CVE-2026-45659 · Vendor Advisory
- https://www.cisa.gov/known-exploited-vulnerabilities-catalog?field_cve=CVE-2026-45659 · US Government Resource
Sources: NVD, CVE.org, FIRST EPSS. Missing ones did not answer or have no record yet.