CVSS 3.1
9.8 criticalCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:HCVE-2025-53770
Critical (9.8) in Microsoft SharePoint. In CISA KEV since 2025-07-20, with known ransomware use. EPSS 100% chance of exploitation in the next 30 days.
Deserialization of untrusted data in on-premises Microsoft SharePoint Server allows an unauthorized attacker to execute code over a network.
Microsoft is aware that an exploit for CVE-2025-53770 exists in the wild.
Microsoft is preparing and fully testing a comprehensive update to address this vulnerability. In the meantime, please make sure that the mitigation provided in this CVE documentation is in place so that you are protected from exploitation.
Severity
- EPSS
- 100% chance of exploitation in the next 30 days; higher than 99% of CVEs (scores of 2026-10-31)
- CISA KEV
- listed 2025-07-20, due 2025-07-21, known ransomware use
- CWE
- CWE-502
- Published
- Modified
- Record from
- the NVD, synced
Affected
- microsoft:sharepoint_server
References
- https://msrc.microsoft.com/update-guide/vulnerability/CVE-2025-53770
- https://arstechnica.com/security/2025/07/sharepoint-vulnerability-with-9-8-severity-rating-is-under-exploit-across-the-globe/
- https://github.com/kaizensecurity/CVE-2025-53770
- https://msrc.microsoft.com/blog/2025/07/customer-guidance-for-sharepoint-vulnerability-cve-2025-53770/
- https://news.ycombinator.com/item?id=44629710