Are Microsoft 365, Exchange & SharePoint safe right now?
No new exploited flaws in the last 30 days, but 2 in the last 90. Make sure those updates are installed.
Exploited in the last 90 days
- SharePointMicrosoft SharePoint Code Injection Vulnerability
What to do: Install the vendor's security update. If there isn't one yet, apply the vendor's workaround, or stop using the product until it's fixed. CISA lists this as actively exploited, so treat it as urgent.
- SharePointMicrosoft SharePoint Weak Authentication Vulnerability
What to do: Install the vendor's security update. If there isn't one yet, apply the vendor's workaround, or stop using the product until it's fixed. CISA lists this as actively exploited, so treat it as urgent.
Earlier exploited flaws
- Microsoft SharePoint Deserialization of Untrusted Data Vulnerability
- Microsoft SharePoint Deserialization of Untrusted Data Vulnerability Zero-day
- Microsoft SharePoint Server Missing Authentication for Critical Function Vulnerability Zero-day
- Microsoft SharePoint Server Deserialization of Untrusted Data Vulnerability
- Microsoft SharePoint Server Improper Input Validation Vulnerability Zero-day
- Microsoft Office Remote Code Execution
- Microsoft Exchange Server Deserialization of Untrusted Data Vulnerability
- Microsoft SharePoint Deserialization of Untrusted Data Vulnerability
- Microsoft Office Word Reliance on Untrusted Inputs in a Security Decision Vulnerability Zero-day
- Microsoft Office Security Feature Bypass Vulnerability Zero-day
- Microsoft Office PowerPoint Code Injection Vulnerability
- Microsoft Office Excel Remote Code Execution Vulnerability
- Microsoft SharePoint Improper Authentication Vulnerability
- Microsoft SharePoint Code Injection Vulnerability
- Microsoft SharePoint Deserialization of Untrusted Data Vulnerability Zero-day
By year
| Year | Exploited flaws added | Zero-days |
|---|---|---|
| 2026 (so far) | 13 | 5 |
| 2025 | 5 | 1 |
| 2024 | 5 | 1 |
| 2023 | 6 | 5 |
| 2022 | 24 | 2 |
Questions
Are Microsoft 365, Exchange & SharePoint safe right now?
No new exploited flaws in the last 30 days, but 2 in the last 90. Make sure those updates are installed. Confirm with the vendor's own advisories and install updates as soon as they're available.
How many Microsoft 365, Exchange & SharePoint vulnerabilities have been exploited?
74 flaws are on CISA's list of vulnerabilities known to be exploited in real attacks, 26 of them used by ransomware.
Covers products matching microsoft, exchange, sharepoint, outlook. Sources: CISA's Known Exploited Vulnerabilities catalog and the vendors' own advisories. Updated every hour. General information only; confirm details with the vendor.