CVE-2021-28480
Microsoft Exchange Server Remote Code Execution Vulnerability
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H/E:U/RL:O/RC:C
Description
Microsoft Exchange Server Remote Code Execution Vulnerability
Official description from the CVE record, published by microsoft. Copyright © 1999-2026 The MITRE Corporation. See /security/cve/legal for the CVE license. View the record on cve.org
Key data
CVSS 3.1 Critical 9.8
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H/E:U/RL:O/RC:C
Attack vector: Network
The vulnerable component can be reached over a network, possibly from the Internet.
Attack complexity: Low
No special conditions are needed. The attack can be repeated at will.
Privileges required: None
No account or privileges are needed.
User interaction: None
No action from any user is needed.
Scope: Unchanged
The impact stays within the vulnerable component.
Confidentiality impact: High
Serious or total effect on the secrecy of data.
Integrity impact: High
Serious or total effect on the trustworthiness of data.
Availability impact: High
Serious or total effect on availability.
| Metric | Value | What it means |
|---|---|---|
| Attack vector | Network | The vulnerable component can be reached over a network, possibly from the Internet. |
| Attack complexity | Low | No special conditions are needed. The attack can be repeated at will. |
| Privileges required | None | No account or privileges are needed. |
| User interaction | None | No action from any user is needed. |
| Scope | Unchanged | The impact stays within the vulnerable component. |
| Confidentiality impact | High | Serious or total effect on the secrecy of data. |
| Integrity impact | High | Serious or total effect on the trustworthiness of data. |
| Availability impact | High | Serious or total effect on availability. |
CVSS is owned and managed by FIRST.Org, Inc. (FIRST) and is used by permission. Each CVSS score on this site is shown together with its vector string, as published in the CVE record by the source named next to it. Learn more at first.org/cvss.
EPSS
- Score
- 0.71227 (71.2% probability)
- Percentile
- 99.4%
- Scores of
- Nov 10, 2026
- Model
- v2026.06.15
Affected products
Microsoft Exchange Server 2013 Cumulative Update 23
- affected: 15.00.0 up to before 15.00.1497.015
Microsoft Exchange Server 2016 Cumulative Update 19
- affected: 15.01.0 up to before 15.01.2176.012
Microsoft Exchange Server 2019 Cumulative Update 8
- affected: 15.02.0 up to before 15.02.0792.013
Microsoft Exchange Server 2016 Cumulative Update 20
- affected: 15.01.0 up to before 15.01.2242.008
Microsoft Exchange Server 2019 Cumulative Update 9
- affected: 15.02.0 up to before 15.02.0858.010
References
Timeline
- ID reserved
- Record published
- Record last updated
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About CubePath
Data from the CVE Program (MITRE), CISA KEV and FIRST EPSS. CVSS is owned by FIRST and used by permission. Not affiliated with or endorsed by MITRE, CISA or FIRST. Data as of Nov 10, 2026, 19:51 UTC. Sources and licenses