On July 20, 2025, CISA issued a high-priority alert regarding a serious vulnerability in Microsoft SharePoint (CVE-2025-53770). This flaw is already being exploited in the wild—meaning if your business uses on-premises SharePoint Server and hasn’t patched yet, you’re potentially exposed.
📌 What is CVE-2025-53770?
This is a remote code execution (RCE) vulnerability affecting Microsoft SharePoint Server. In simple terms, attackers can remotely execute arbitrary code on your server without needing valid credentials. They could gain access, deploy malware, steal data, or pivot deeper into your network.
Microsoft has confirmed exploitation is actively occurring. Translation? This isn’t theoretical. It’s happening now.
☁️ Does This Affect SharePoint Online?
No. SharePoint Online is not impacted.
This vulnerability only affects on-premises versions of SharePoint, including:
SharePoint Server Subscription Edition
SharePoint Server 2019
SharePoint Server 2016
SharePoint Online, part of Microsoft 365, is managed and patched directly by Microsoft. As long as you are not using a hybrid deployment with unpatched on-prem servers, you are not exposed to CVE-2025-53770.
🔥 Why This Matters
SharePoint is core infrastructure for many businesses—used for collaboration, document management, and storing sensitive data. A vulnerability like this opens the door to:
Data breaches
Business email compromise (BEC)
Lateral movement across your network
Ransomware deployment
If your organization relies on SharePoint Server and hasn’t applied the latest updates, you’re at real risk.
🛡️ What You Should Do Immediately
Boston Managed IT recommends the following steps for on-premises SharePoint environments:
Patch Now
Apply Microsoft’s July 2025 updates for SharePoint Server to mitigate the vulnerability.Audit Your SharePoint Server
Review:External access permissions
Admin privilege assignments
Any unusual login activity or unrecognized accounts
Scan for Indicators of Compromise (IOCs)
Use CISA’s list of IOCs to identify potential intrusion. We can help run these scans and assess any exposure.Enable Threat Detection
Ensure your EDR platform is monitoring all SharePoint server activity.Harden the Environment
Enforce least-privilege access, enable MFA, and segment your SharePoint servers from the broader network.
🧭 How Boston Managed IT Can Help
As a trusted cybersecurity partner, we specialize in:
Proactive patch management and system audits
Threat detection and incident response
SharePoint Server hardening
Fully managed IT and cybersecurity for small and midsize businesses
If you’re unsure whether your SharePoint environment is vulnerable, schedule a free risk assessment call today.
