9.1

CVE-2021-27078: microsoft exchange_server

CVSS: 9.1v3.1CriticalModified
Published 02-03-2021Last modified 19-08-2026
Open JSON

Vulnerability summary

CVE-2021-27078 is a critical (CVSS 9.1) vulnerability in microsoft exchange_server. EPSS estimates a 21.59% chance of exploitation in the next 30 days, higher than 97.6% of scored vulnerabilities.

Overall risk
70/100
0100
High · default modelHow is this calculated?
CVSS score
9.1/10
010
Critical · v3.1 (CVE.org)
EPSS score
21.59%
0%100%
High · +1.03 pp in 30 days
KEVNot listedIn no KEV catalog
RansomwareNone recordedNo known use recorded
Public exploits0No public exploits recorded

Timeline

  1. 02-03-2021
    PublishedVulnerability first disclosed.
  2. 19-08-2026
    Last modifiedVulnerability information updated.

Description

Microsoft Exchange Server Remote Code Execution Vulnerability

CVSS metrics

3 scores · 2 sources · 2 versions

EPSS trend

Probability

21.59%

Chance of exploitation in the next 30 days

Percentile

98%

Versus all other CVEs

30-day change

+1.03 pp

From 20.56% on 20-09-2026

20-09-202620-10-2026
EPSS score
21.59%

Known exploited

Compare KEV catalogs

Not in any of the 3 tracked catalogs.

Public exploits

0 found

No public exploits indexed.

Weaknesses

CWE · root cause

No weakness data has been published for this record.

Affected systems

Microsoft6 products

1 vendor · 6 products

References

2 links