Critical Unpatched Microsoft SharePoint Zero-Day Exploit Affects Over 75 Global Organizations
TL;DR
A critical zero-day vulnerability (CVE-2025-53770) in Microsoft SharePoint Server is being actively exploited, affecting over 75 organizations globally. This flaw, a variant of a previously patched spoofing bug (CVE-2025-49706), poses significant security risks.
Introduction
A severe security vulnerability in Microsoft SharePoint Server has been exploited in a large-scale campaign, impacting numerous organizations worldwide. This zero-day flaw, identified as CVE-2025-53770, is a variant of a previously addressed spoofing bug (CVE-2025-49706) and has a CVSS score of 9.8, indicating a critical risk.
Overview of the Vulnerability
Technical Details
- CVE-2025-53770: This zero-day vulnerability allows attackers to exploit Microsoft SharePoint Server, leading to potential data breaches and system compromises.
- CVSS Score: 9.8, highlighting the critical nature of the flaw.
- Relation to Previous Bug: This vulnerability is a variant of CVE-2025-49706, a spoofing bug addressed in Microsoft’s July 2025 Patch Tuesday.
Impact and Exploitation
The vulnerability has been actively exploited in a widespread campaign, affecting over 75 organizations globally. The exploitation involves sophisticated techniques that bypass existing security measures, making it a significant concern for cybersecurity professionals.
Conclusion
The exploitation of the CVE-2025-53770 vulnerability underscores the importance of timely patching and vigilant cybersecurity practices. Organizations using Microsoft SharePoint Server should prioritize applying the necessary security updates to mitigate the risk associated with this critical flaw.
Additional Resources
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