VulnerabilityModified
CVE-2021-31209
Microsoft Exchange Server Spoofing Vulnerability
MEDIUM 6.5EPSS 2.63%
Does this matter?
Lower severity and a low EPSS score (2.63%). Track it; it rarely justifies an emergency change on its own.
Description
Microsoft Exchange Server Spoofing Vulnerability
- CVSS 3.1
- 6.5 MEDIUMCVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:L/A:N
- EPSS
- 2.63% probability · 85th percentile
- Public exploits
- None in Exploit-DB
- CISA KEV
- Not listed
- Weakness
- CWE-290
- Affected
- microsoft/exchange server
- Source
- secure@microsoft.com
EPSS 2.6% since 26 October 2026; no change recorded yet. Points are recorded when the score first appears and whenever it moves by a percentage point or more.
References
- https://portal.msrc.microsoft.com/en-US/security-guidance/advisory/CVE-2021-31209Patch, Vendor Advisory
- https://www.zerodayinitiative.com/advisories/ZDI-21-615/Third Party Advisory, VDB Entry
- https://portal.msrc.microsoft.com/en-US/security-guidance/advisory/CVE-2021-31209Patch, Vendor Advisory
- https://www.zerodayinitiative.com/advisories/ZDI-21-615/Third Party Advisory, VDB Entry
Source: NVD record, EPSS from FIRST.org, KEV from CISA, exploits from Exploit-DB. Refreshed daily. Download this record as JSON.