Microsoft Exchange Server Elevation of Privilege Vulnerability
Priority LOW 37Published · Updated
Key facts
- Attack vector
- Adjacent network
- Privileges required
- Low
- User interaction
- None
- Attack complexity
- Low
- Impact type
- Privilege escalation
- Confidentiality · integrity · availability
- High · High · High
- Fix status
- Fixed
Attack profile from CVSS 3.1 · CNA. Fix status from CNA and Microsoft. Impact type from Microsoft.
Summary
Microsoft Exchange Server Elevation of Privilege Vulnerability
Why it matters now
EPSS 0.01235 69th percentileScored 2026-11-07
Fix Fixed Microsoft: 2 updates
SSVC decision points
Not available: CISA has not published SSVC decision points for this record.
Affected products
| Vendor | Product | Affected versions | Fixed in | Status | Source |
|---|---|---|---|---|---|
| Microsoft | Microsoft Exchange Server 2016 Cumulative Update 20 | 15.01.0 to before 15.01.2242.012 | 15.01.2242.012 | Patch available | CNA |
| Microsoft | Microsoft Exchange Server 2016 Cumulative Update 21 | 15.01.0 to before 15.01.2308.014 | 15.01.2308.014 | Patch available | CNA |
| Microsoft | Microsoft Exchange Server 2019 Cumulative Update 10 | 15.02.0 to before 15.02.0922.013 | 15.02.0922.013 | Patch available | CNA |
| Microsoft | Microsoft Exchange Server 2019 Cumulative Update 9 | 15.02.0 to before 15.02.0858.015 | 15.02.0858.015 | Patch available | CNA |
- Microsoft Exchange Server 2016 Cumulative Update 20 VendorMicrosoft Affected 15.01.0 to before 15.01.2242.012 Fixed in 15.01.2242.012 Patch available CNA
- Microsoft Exchange Server 2016 Cumulative Update 21 VendorMicrosoft Affected 15.01.0 to before 15.01.2308.014 Fixed in 15.01.2308.014 Patch available CNA
- Microsoft Exchange Server 2019 Cumulative Update 10 VendorMicrosoft Affected 15.02.0 to before 15.02.0922.013 Fixed in 15.02.0922.013 Patch available CNA
- Microsoft Exchange Server 2019 Cumulative Update 9 VendorMicrosoft Affected 15.02.0 to before 15.02.0858.015 Fixed in 15.02.0858.015 Patch available CNA
CPE configurations NVD · 4
| CPE | Versions | Role | Vendor |
|---|---|---|---|
| cpe:2.3:a:microsoft:exchange_server:2016:cumulative_update_20:*:*:*:*:*:* | 2016 cumulative_update_20 | Vulnerable | Microsoft |
| cpe:2.3:a:microsoft:exchange_server:2016:cumulative_update_21:*:*:*:*:*:* | 2016 cumulative_update_21 | Vulnerable | Microsoft |
| cpe:2.3:a:microsoft:exchange_server:2019:cumulative_update_10:*:*:*:*:*:* | 2019 cumulative_update_10 | Vulnerable | Microsoft |
| cpe:2.3:a:microsoft:exchange_server:2019:cumulative_update_9:*:*:*:*:*:* | 2019 cumulative_update_9 | Vulnerable | Microsoft |
- cpe:2.3:a:microsoft:exchange_server:2016:cumulative_update_20:*:*:*:*:*:* Versions 2016 cumulative_update_20 Vulnerable ·Microsoft
- cpe:2.3:a:microsoft:exchange_server:2016:cumulative_update_21:*:*:*:*:*:* Versions 2016 cumulative_update_21 Vulnerable ·Microsoft
- cpe:2.3:a:microsoft:exchange_server:2019:cumulative_update_10:*:*:*:*:*:* Versions 2019 cumulative_update_10 Vulnerable ·Microsoft
- cpe:2.3:a:microsoft:exchange_server:2019:cumulative_update_9:*:*:*:*:*:* Versions 2019 cumulative_update_9 Vulnerable ·Microsoft
Remediation
Microsoft 2 updates
- Security Update
- Microsoft Exchange Server 2019 Cumulative Update 10 15.02.0922.013
- Microsoft Exchange Server 2019 Cumulative Update 9 15.02.0858.015
- Security Update
- Microsoft Exchange Server 2016 Cumulative Update 20 15.01.2242.012
- Microsoft Exchange Server 2016 Cumulative Update 21 15.01.2308.014
Vendor assessments
Microsoft
Microsoft's page for this CVE →
- Impact
- Elevation of Privilege
- Exploited
- No
- Publicly disclosed
- No
- Exploitability
- Exploitation Less Likely
Timeline
- 2026-10-02 Threatist record created from CVE-2021-33768
- 2026-10-03 Alias added: GHSA-79w4-597w-fxxx
References
More Microsoft Exchange Server vulnerabilities
- TI-2024-14170 Microsoft Exchange Server Elevation of Privilege Vulnerability KEVCVSS 3.1CRITICAL 9.8
- TI-2022-19610 Microsoft Exchange Server Elevation of Privilege Vulnerability KEVCVSS 3.1CRITICAL 9.8
- TI-2021-13547 Microsoft Exchange Server Elevation of Privilege Vulnerability KEVCVSS 3.1CRITICAL 9.8
- TI-2021-13502 Microsoft Exchange Server Remote Code Execution Vulnerability KEVCVSS 3.1CRITICAL 9.8
- TI-2021-08465 Microsoft Exchange Server Remote Code Execution Vulnerability KEVCVSS 3.1CRITICAL 9.8
- TI-2023-07929 Microsoft Exchange Server Remote Code Execution Vulnerability KEVCVSS 3.1HIGH 8.8
Sources
- CVE-2021-33768 · CVE Program
- CVE-2021-33768 · NVD
- FIRST EPSS
- GHSA-79w4-597w-fxxx · GitHub Advisory Database · CC BY 4.0
- CVE-2021-33768 · Microsoft Security Update Guide
This product uses the NVD API but is not endorsed or certified by the NVD. Sources and licences