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CVE-2021-33766Microsoft Exchange Server Information Disclosure Vulnerability

Microsoft Exchange Server Information Disclosure Vulnerability

7.3 HIGHEPSS 98.17%⚡ Known Exploited (CISA KEV)NVD: Published

Last updated: 2026-08-10 15:11 UTC

OverviewCVSS details

7.3HIGHCVSS 3.1

Score source: microsoft (CNA)
NVD status: Published
Published: Jul 14, 2021
Assigner: microsoft

Affected

Microsoft Exchange Server 2013 Cumulative Update 23 (Microsoft)

Versions: 15.00.0 before 15.00.1497.015
Fixed in: 15.00.1497.015

+4 more products →

Exploitation

Public exploit: None listed
CISA KEV: Listed · Jan 18, 2022
KEV due date: Feb 1, 2022
Ransomware use: Unknown
SSVC: Exploitation active · Automatable yes · Impact partial

EPSS · FIRST, scored Nov 6

98.17%chance of exploitation in 30 days

Higher than 99.91% of CVEs

CVSS 3.1 · microsoft (CNA)

7.3High

CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:L/A:L/E:U/RL:O/RC:C

Attack vector: Network
Attack complexity: Low
Privileges required: None
User interaction: None
Scope: Unchanged
Confidentiality impact: Low
Integrity impact: Low
Availability impact: Low

NVD status: Published

Overview Affected Products References

Overview

Severity

Score	Severity	Version	Vector String
7.3	HIGH	3.1microsoft (CNA)	CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:L/A:L/E:U/RL:O/RC:C

Details

CVE ID: CVE-2021-33766
Status: Published
Assigner (CNA): microsoft
Published: Jul 14, 2021
Last modified: 2026-08-10 15:11 UTC
Weaknesses: CWE-287

Sources

NVD (unavailable at last refresh)
CVE.org
CISA KEV
FIRST EPSS

Refreshed hourly from the sources above. Last fetched 2026-11-07 14:12 UTC.