CVE-2021-26854
Microsoft Exchange Server Remote Code Execution Vulnerability
Microsoft Exchange Server Remote Code Execution Vulnerability
Attack profile
How easy it is to exploit
- Attack vector
- Network
- Complexity
- High
- Privileges needed
- High
- User interaction
- None
What an attacker can affect
- Confidentiality
- High
- Integrity
- High
- Availability
- High
Exploit likelihood
What each source reports
CVE List Score used
Microsoft Exchange Server Remote Code Execution Vulnerability
Microsoft Exchange Server Remote Code Execution Vulnerability
- Record
CVE-2021-26854- CVSS 3.1
- 6.6 Medium
CVSS:3.1/AV:N/AC:H/PR:H/UI:N/S:U/C:H/I:H/A:H/E:U/RL:O/RC:C - Updated
- 2026-11-02
EUVDEUVD-2021-13638
Microsoft Exchange Server Remote Code Execution Vulnerability
- Record
EUVD-2021-13638- CVSS 3.1
- 6.6 Medium
CVSS:3.1/AV:N/AC:H/PR:H/UI:N/S:U/C:H/I:H/A:H/E:U/RL:O/RC:C - Updated
- 2026-11-02
GitHub AdvisoriesGHSA-2xf7-r7hp-r5qc
Microsoft Exchange Server Remote Code Execution Vulnerability This CVE ID is unique from CVE-2021...
Microsoft Exchange Server Remote Code Execution Vulnerability This CVE ID is unique from CVE-2021-26412, CVE-2021-26855, CVE-2021-26857, CVE-2021-26858, CVE-2021-27065, CVE-2021-27078.
- Record
GHSA-2xf7-r7hp-r5qc- CVSS 3.1
- 6.6 Medium
CVSS:3.1/AV:N/AC:H/PR:H/UI:N/S:U/C:H/I:H/A:H - Updated
- 2026-11-02
NVD
Microsoft Exchange Server Remote Code Execution Vulnerability
- Record
CVE-2021-26854- CVSS 3.1
- 6.6 Medium
CVSS:3.1/AV:N/AC:H/PR:H/UI:N/S:U/C:H/I:H/A:H - CVSS 3.1
- 7.2 High
CVSS:3.1/AV:N/AC:L/PR:H/UI:N/S:U/C:H/I:H/A:H - CVSS 2.0
- 6.5 Medium
AV:N/AC:L/Au:S/C:P/I:P/A:P - Updated
- 2026-11-02
Affected products
History
| Recorded | Changed | Sources |
|---|---|---|
| first indexed | CVE List, EUVD, GitHub Advisories, NVD |
Dates are when Every CVE recorded each change. Upstream dates may differ.
In short
CVE-2021-26854 is a medium vulnerability (CVSS 6.6) in Microsoft Exchange Server, published March 2, 2021. No source lists public exploit code. EPSS puts the chance of exploitation in the next 30 days at 24.7%, the 97th percentile. No source names a fixed version.