CVE Catalog
Actively exploited in the wild
Microsoft Exchange Server Remote Code Execution Vulnerability
Microsoft - Exchange Server · Listed in the CISA KEV since 2021-11-03. This indicates confirmed attacks in production environments.
Required action: Apply updates per vendor instructions.
CVE-2021-26858
HighCVSS 7.8KEVExploitation Probability (EPSS)
Very high risk89.51%
100th percentile - higher than 100% of all known CVEs
Summary
A remote code execution vulnerability in Microsoft Exchange Server allows an attacker to execute arbitrary code on the server.
Risk Assessment
An attacker could gain full control of the Exchange server, leading to data theft, malware installation, and service disruption.
Recommendation
Apply Microsoft's security updates for Exchange Server immediately and audit the system for compromise.
Original NVD description (English source)
Microsoft Exchange Server Remote Code Execution Vulnerability