CVE-2021-26858

Microsoft Exchange Server Remote Code Execution Vulnerability

State: Published
Severity: 7.8 High
Published: Mar 2, 2021
Updated: Oct 1, 2026
Reserved: Feb 8, 2021

Description

Microsoft Exchange Server Remote Code Execution Vulnerability

Scores

CVSS	Score	Vector	Source
3.1	7.8 High	CVSS:3.1/AV:L/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:H/E:F/RL:O/RC:C	microsoft

Weaknesses

The record names no weakness.

Affected Products

Product	Versions
Microsoft Exchange Server 2013 Cumulative Update 21Microsoft	15.00.0 to before 15.00.1395.012Affected
Microsoft Exchange Server 2013 Cumulative Update 22Microsoft	15.00.0 to before 15.00.1473.006Affected
Microsoft Exchange Server 2013 Cumulative Update 23Microsoft	15.00.0 to before 15.00.1497.012Affected
Microsoft Exchange Server 2016 Cumulative Update 10Microsoft	15.01.0 to before 15.01.1531.012Affected
Microsoft Exchange Server 2016 Cumulative Update 11Microsoft	15.01.0 to before 15.01.1591.018Affected
Microsoft Exchange Server 2016 Cumulative Update 12Microsoft	15.01.0 to before 15.01.1713.010Affected
Microsoft Exchange Server 2016 Cumulative Update 13Microsoft	15.01.0 to before 15.01.1779.008Affected
Microsoft Exchange Server 2016 Cumulative Update 14Microsoft	15.01.0 to before 15.01.1847.012Affected
Microsoft Exchange Server 2016 Cumulative Update 15Microsoft	15.01.0 to before 15.01.1913.012Affected
Microsoft Exchange Server 2016 Cumulative Update 16Microsoft	15.01.0 to before 15.01.1979.008Affected
Microsoft Exchange Server 2016 Cumulative Update 17Microsoft	15.01.0 to before 15.01.2044.013Affected
Microsoft Exchange Server 2016 Cumulative Update 18Microsoft	15.01.0 to before 15.01.2106.013Affected
Microsoft Exchange Server 2016 Cumulative Update 19Microsoft	15.01.0 to before 15.01.2176.009Affected
Microsoft Exchange Server 2016 Cumulative Update 8Microsoft	15.01.0 to before 15.01.1415.010Affected
Microsoft Exchange Server 2016 Cumulative Update 9Microsoft	15.01.0 to before 15.01.1466.016Affected
Microsoft Exchange Server 2019Microsoft	15.02.0 to before 15.02.0221.018Affected
Microsoft Exchange Server 2019 Cumulative Update 1Microsoft	15.02.0 to before 15.01.1979.006Affected
Microsoft Exchange Server 2019 Cumulative Update 2Microsoft	15.02.0 to before 15.02.0397.011Affected
Microsoft Exchange Server 2019 Cumulative Update 3Microsoft	15.02.0 to before 15.02.0464.015Affected
Microsoft Exchange Server 2019 Cumulative Update 4Microsoft	15.02.0 to before 15.02.0659.012Affected
Microsoft Exchange Server 2019 Cumulative Update 5Microsoft	15.02.0 to before 15.02.0595.008Affected
Microsoft Exchange Server 2019 Cumulative Update 6Microsoft	15.02.0 to before 15.02.0529.013Affected
Microsoft Exchange Server 2019 Cumulative Update 7Microsoft	15.02.0 to before 15.02.0721.013Affected
Microsoft Exchange Server 2019 Cumulative Update 8Microsoft	15.02.0 to before 15.02.0792.010Affected

References

Microsoft Exchange Server Remote Code Execution Vulnerabilityvendor-advisorypatch
https://portal.msrc.microsoft.com/en-US/security-guidance/advisory/CVE-2021-26858
https://www.cisa.gov/known-exploited-vulnerabilities-catalog?field_cve=CVE-2021-26858government-resource

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