Vulnerability Intelligence Report
Microsoft Exchange Server Remote Code Execution Vulnerability
CVE-2021-34473
Microsoft Exchange Server Remote Code Execution Vulnerability
CISA KEV
Nuclei Template
SSVC: Active Exploitation
Automatable
CVSS Base Score
9.1
CRITICAL
Exploitability:3.9
Impact Score:5.2
EPSS Probability:100.00%
Executive Threat Verdict
Evaluating...
Evaluating Threat Landscape...
Assessing known weaponization, exploitation telemetry, and federal advisories.
Attack Surface
—
Authentication
—
Weaponization
—
SSVC Action
—
Weaknesses (CWE)
CWE-918 ↗CWE-918 Server-Side Request Forgery (SSRF)
Affected Products & Versions
| Vendor | Product | Affected Versions |
|---|---|---|
| Microsoft | Microsoft Exchange Server 2013 Cumulative Update 23 | 15.00.0 < 15.00.1497.015 (affected) |
| Microsoft | Microsoft Exchange Server 2016 Cumulative Update 19 | 15.01.0 < 15.01.2176.012 (affected) |
| Microsoft | Microsoft Exchange Server 2016 Cumulative Update 20 | 15.01.0 < 15.01.2242.008 (affected) |
| Microsoft | Microsoft Exchange Server 2019 Cumulative Update 8 | 15.02.0 < 15.02.0792.013 (affected) |
| Microsoft | Microsoft Exchange Server 2019 Cumulative Update 9 | 15.02.0 < 15.02.0858.010 (affected) |
References & Technical Advisories
No reference links found.
Threat Intelligence Signals
CISA KEV
ACTIVE IN CATALOG
Nuclei Template
SCANNER AVAILABLE
EPSS Score
99.999%
GitHub Advisory
Identity & Timeline
| Status | PUBLISHED |
| Assigning Authority | Microsoft Corporation · Vendor · USA |
| Reserved | 2021-06-09T00:00:00 |
| Published | 2021-07-14T17:54:03 |
| Patch Date | 2021-07-13 |
| Last Updated | 2026-08-10T15:11:21 |
Community Chatter & Buzz