CVE-2021-31209

Microsoft Exchange Server Spoofing Vulnerability

Description

Microsoft Exchange Server Spoofing Vulnerability

Category

6.5
CVSS
Severity: Medium
CVSS 3.1 •
CVSS 2.0 •
EPSS 0.49%
Vendor Advisory microsoft.com
Affected: Microsoft Microsoft Exchange Server 2019 Cumulative Update 9
Affected: Microsoft Microsoft Exchange Server 2016 Cumulative Update 20
Affected: Microsoft Microsoft Exchange Server 2013 Cumulative Update 23
Affected: Microsoft Microsoft Exchange Server 2016 Cumulative Update 19
Affected: Microsoft Microsoft Exchange Server 2019 Cumulative Update 8
Published at:
Updated at:

References

Link Tags
https://portal.msrc.microsoft.com/en-US/security-guidance/advisory/CVE-2021-31209 patch vendor advisory
https://www.zerodayinitiative.com/advisories/ZDI-21-615/ third party advisory vdb entry

Frequently Asked Questions

What is the severity of CVE-2021-31209?
CVE-2021-31209 has been scored as a medium severity vulnerability.
How to fix CVE-2021-31209?
To fix CVE-2021-31209, make sure you are using an up-to-date version of the affected component(s) by checking the vendor release notes. As for now, there are no other specific guidelines available.
Is CVE-2021-31209 being actively exploited in the wild?
As for now, there are no information to confirm that CVE-2021-31209 is being actively exploited. According to its EPSS score, there is a ~0% probability that this vulnerability will be exploited by malicious actors in the next 30 days.
What software or system is affected by CVE-2021-31209?
CVE-2021-31209 affects Microsoft Microsoft Exchange Server 2019 Cumulative Update 9, Microsoft Microsoft Exchange Server 2016 Cumulative Update 20, Microsoft Microsoft Exchange Server 2013 Cumulative Update 23, Microsoft Microsoft Exchange Server 2016 Cumulative Update 19, Microsoft Microsoft Exchange Server 2019 Cumulative Update 8.
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