Skip to main content

CVE-2021-33766

7.3
HIGHCVSS v3.1 Base Score
93.75%
HIGH RiskEPSS (100th percentile)
KEV
NVD-CWE-noinfo

Microsoft Exchange Server Information Disclosure Vulnerability

Published: 7/14/2021
Modified: 10/29/2025
Back to CVE Lookup

ACTIVELY EXPLOITED IN THE WILD

This vulnerability is listed in the CISA Known Exploited Vulnerabilities (KEV) catalog.

Vulnerability Name:

Microsoft Exchange Server Information Disclosure

Vendor / Product:

Microsoft Exchange Server

Required Action:

Apply updates per vendor instructions.

Due Date: 2/1/2022(OVERDUE)
Added to KEV:

1/18/2022

Notes:

https://nvd.nist.gov/vuln/detail/CVE-2021-33766

Vulnerability Summary

CVSS v3 Score

7.3HIGH

CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:L/A:L

CVSS v2 Score

5

AV:N/AC:L/Au:N/C:P/I:N/A:N

EPSS Score (Exploitation Probability)

93.75%HIGH Exploitation Risk
100th percentile

This vulnerability has a 93.75% probability of being exploited in the next 30 days, ranking higher than 100% of all scored CVEs.

CWE Classification

NVD-CWE-noinfo

Related Vulnerabilities