Microsoft Exchange Server Spoofing Vulnerability

published 2021-02-25 5y ago modified 2026-06-17 4mo ago also EUVD-2021-11001

cvss: 6.5; version 3.1, CNA
cisa kev: Not listed; not in CISA's catalog
epss: 4.6%; EPSS 4.6% chance of exploitation in 30 days, percentile 91%
public exploits: 0; none known

Patch / fix

links 1

portal.msrc.microsoft.com/en-US/security-guidance/advisory/CVE-2021-24085 advisory

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Exploit prediction

4.63% chance of exploitation in the next 30 days, higher than 91% of all scored CVEs (FIRST EPSS, 2026-11-09).

CVSS scores

assigned by	version	score	vector
CNA	3.1	6.5	CVSS:3.1/AV:N/AC:L/PR:L/UI:R/S:C/C:L/I:L/A:L/E:U/RL:O/RC:C
CNA	3.1	6.5	CVSS:3.1/AV:N/AC:L/PR:L/UI:R/S:C/C:L/I:L/A:L
CNA	3.1	5.5	CVSS:3.1/AV:N/AC:L/PR:L/UI:R/S:U/C:L/I:L/A:L
NVD	2.0	6.0	AV:N/AC:M/Au:S/C:P/I:P/A:P

Affected products

Microsoft Microsoft Exchange Server 2019 Cumulative Update 8
Microsoft Microsoft Exchange Server 2016 Cumulative Update 19
Microsoft Microsoft Exchange Server 2019 Cumulative Update 7
Microsoft Microsoft Exchange Server 2016 Cumulative Update 18

Classification

Technology feeds

Microsoft Exchange rss critical rss

References

portal.msrc.microsoft.com /en-US/security-guidance/advisory/CVE-2021-24085
patch, vendor-advisory

Sources

CVE List CVE-2021-24085
NVD CVE-2021-24085

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