Microsoft Office and SharePoint: Multiple High-Severity Vulnerabilities
The NCSC-NL has identified multiple high-severity vulnerabilities in Microsoft Office, specifically within SharePoint, which could permit unauthorized code execution, sensitive data access, or system impersonation.
Triage facts
Revision 1- Applicability
- SharePoint, Microsoft Office
- Evidence
- Unknown
- Severity
- High
- Action
- Elevated
- Sources
- 1 public source
- Freshness
- Revision 1Nov 11, 13:53 UTC
- Source quality
- A1Roughly even chance
The National Cyber Security Centre (NCSC-NL) has reported multiple critical vulnerabilities affecting Microsoft Office, with three specific vulnerabilities in SharePoint rated with a CVSS score of 9.0 or higher. Attackers could potentially leverage these flaws to impersonate users, execute arbitrary code, or access sensitive information. There is no evidence of active exploitation at this time.
Impact
Unpatched systems are at risk of arbitrary code execution, unauthorized access to sensitive information, and full system compromise. This poses a significant threat to data confidentiality and business continuity.
Recommendation
- Immediately review internal inventory for all Microsoft Office and SharePoint instances.
- Apply security updates provided by Microsoft for all affected installations as a priority.
- Contact managed IT service providers if internal patch management processes require validation.
Immediate actions
Patch all SharePoint and Office environments using the latest security updates provided by Microsoft
Threat Hunt
Monitor SharePoint access logs for unusual administrative activity or successful logins from atypical IP addresses
Data: SharePoint Unified Audit Logs
Mitigations
Apply Microsoft security updates
SharePoint and Office vulnerabilities