Medium severity · published May 11, 2021
CVE-2021-31209
Microsoft Exchange Server Spoofing Vulnerability
6.5
CVSS
2.6%
EPSS
No
On KEV
CVSS vector
CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:L/A:N
Attack vector
Network
Complexity
High
Privileges
None
User interaction
None
Confidentiality
High
Integrity
Low
Availability
None
Scope
Unchanged
Exploitation
Is it being used?
Exploit prediction (EPSS)2.6% · higher than 85% of CVEs
Exploited in the wildNo evidence yet
CISA KEVNot listed
Ransomware campaign useNot known
Affected products
Which versions
ES
Exchange Server · Microsoft
2013; 2016; 2016; 2019; 2019 · source: NVD
References
NVD
https://nvd.nist.gov/vuln/detail/CVE-2021-31209
CVE.org
https://www.cve.org/CVERecord?id=CVE-2021-31209
Patch
https://portal.msrc.microsoft.com/en-US/security-guidance/advisory/CVE-2021-31209
Third Party Advisory
https://www.zerodayinitiative.com/advisories/ZDI-21-615/
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