VulnTideExploited vulnerabilities, by vendor. Data as of .
Not in CISA KEVReported exploited: VulnCheck KEV since Published CVSS 7.6 highEPSS 13% probability of exploitation in 30 days
Microsoft

CVE-2021-31206: Microsoft Exchange Server Remote Code Execution Vulnerability

Is it exploited?

Reported, not confirmed by CISA. VulnCheck KEV lists it as exploited in the wild. CISA has not added it to its Known Exploited Vulnerabilities catalog as of .

VulnCheck KEV lists it since . It cites 8 public reports, the first from .

How likely is exploitation in the next 30 days?
13%

EPSS score, percentile 96.3 of all scored records. A probability estimated by FIRST, not a report of exploitation.

How severe?
7.6 High

CVSS v3.1 base score, given by the CNA

What should I do?

CISA has set no required action, because the vulnerability is not in KEV.

Advisories and patches (1)

Which versions are affected?

Affected

  • from 15.00.0 to before 15.00.1497.023
  • from 15.01.0 to before 15.01.2242.012
  • from 15.01.0 to before 15.01.2308.014
  • from 15.02.0 to before 15.02.0922.013
  • from 15.02.0 to before 15.02.0858.015

Versions by product

Source: CISA KEV 2026.10.29, as of ; VulnCheck KEV, as of ; FIRST EPSS, as of ; CVE List, as of . About the data.

Description

Microsoft Exchange Server Remote Code Execution Vulnerability

Microsoft Exchange Server Remote Code Execution Vulnerability

Source: CVE List, as of . About the data.

What to do

Advisories and patches

This summary is based on the CVE record as of . Check the vendor's advisory before you act: affected versions and fixes can change.

Affected products and versions

Versions by product, as listed in the CVE record (5 products)
Microsoft Microsoft Exchange Server 2013 Cumulative Update 23
StatusVersions
Affectedfrom 15.00.0 to before 15.00.1497.023
Microsoft Microsoft Exchange Server 2016 Cumulative Update 20
StatusVersions
Affectedfrom 15.01.0 to before 15.01.2242.012
Microsoft Microsoft Exchange Server 2016 Cumulative Update 21
StatusVersions
Affectedfrom 15.01.0 to before 15.01.2308.014
Microsoft Microsoft Exchange Server 2019 Cumulative Update 10
StatusVersions
Affectedfrom 15.02.0 to before 15.02.0922.013
Microsoft Microsoft Exchange Server 2019 Cumulative Update 9
StatusVersions
Affectedfrom 15.02.0 to before 15.02.0858.015

Source: CVE List, as of . About the data.

Timeline

DateEvent
CVE record published
CVE record last updated

Known exploited Microsoft vulnerabilities

  • CVE-2026-96951: Microsoft Windows Command Injection Vulnerability (added )
  • CVE-2026-65660: Microsoft SharePoint Code Injection Vulnerability (added )
  • CVE-2026-81963: Microsoft Windows Link Following Vulnerability (added )
  • CVE-2026-85880: Microsoft Windows Heap-Based Buffer Overflow Vulnerability (added )
  • CVE-2019-1068: Microsoft SQL Server Remote Code Execution Vulnerability (added )