Known exploited · Microsoft
CVE-2025-49706: Microsoft SharePoint Improper Authentication Vulnerability
What it is
Microsoft SharePoint contains an improper authentication vulnerability that allows an authorized attacker to perform spoofing over a network. Successfully exploitation could allow an attacker to view sensitive information and make some changes to disclosed information. This vulnerability could be chained with CVE-2025-49704. CVE-2025-53771 is a patch bypass for CVE-2025-49706, and the updates for CVE-2025-53771 include more robust protection than those for CVE-2025-49706.
- Vendor
- Microsoft
- Product
- SharePoint
- Added to KEV
- July 22, 2025
- CISA due date
- July 23, 2025
- Ransomware use
- Known
- Weakness
- CWE-287: Improper Authentication
What CISA requires
Disconnect public-facing versions of SharePoint Server that have reached their end-of-life (EOL) or end-of-service (EOS) to include SharePoint Server 2013 and earlier versions. For supported versions, please follow the mitigations according to CISA (URL listed below in Notes) and vendor instructions (URL listed below in Notes). Adhere to the applicable BOD 22-01 guidance for cloud services or discontinue use of the product if mitigations are not available.
Forensic triage
No
What to do now
- Find every instance of SharePoint you run, including the forgotten ones, and check its version against the vendor advisory.
- Apply the vendor's fix or mitigation, before July 23, 2025 if you are bound by CISA's deadline, sooner if it faces the internet.
- Assume it was tried against you already: look for signs of exploitation from the date it was added, not from the day you patched.
References
H2 Security
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Start freeSource: CISA Known Exploited Vulnerabilities Catalog (public domain), catalog version 2026.10.01.