9.8

CVE-2023-21709: microsoft exchange_server

CVSS: 9.8v3.1CriticalModified
Published 08-08-2023Last modified 10-08-2026
Open JSON

Vulnerability summary

CVE-2023-21709 is a critical (CVSS 9.8) vulnerability in microsoft exchange_server. EPSS estimates a 1.98% chance of exploitation in the next 30 days, higher than 80.2% of scored vulnerabilities.

Overall risk
70/100
0100
High · default modelHow is this calculated?
CVSS score
9.8/10
010
Critical · v3.1 (CVE.org)
EPSS score
1.98%
0%100%
Low · 0.00 pp in 30 days
KEVNot listedIn no KEV catalog
RansomwareNone recordedNo known use recorded
Public exploits0No public exploits recorded

Timeline

  1. 08-08-2023
    PublishedVulnerability first disclosed.
  2. 10-08-2026
    Last modifiedVulnerability information updated.

Description

Microsoft Exchange Server Elevation of Privilege Vulnerability

CVSS metrics

2 scores · 2 sources · 1 version

EPSS trend

Probability

1.98%

Chance of exploitation in the next 30 days

Percentile

80%

Versus all other CVEs

30-day change

0.00 pp

From 1.98% on 20-09-2026

20-09-202620-10-2026
EPSS score
1.98%

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

Affected systems

Microsoft4 products
  • exchange_serverEOL2016 | 2016:cumulative_update_1 | 2016:cumulative_update_10 | 2016:cumulative_update_11 | 2016:cumulative_update_12 | 2016:cumulative_update_13 | 2016:cumulative_update_14 | 2016:cumulative_update_15 | 2016:cumulative_update_16 | 2016:cumulative_update_17 | 2016:cumulative_update_18 | 2016:cumulative_update_19 | 2016:cumulative_update_2 | 2016:cumulative_update_20 | 2016:cumulative_update_21 | 2016:cumulative_update_22 | 2016:cumulative_update_3 | 2016:cumulative_update_4 | 2016:cumulative_update_5 | 2016:cumulative_update_6 | 2016:cumulative_update_7 | 2016:cumulative_update_8 | 2016:cumulative_update_9 | 2019 | 2019:cumulative_update_1 | 2019:cumulative_update_10 | 2019:cumulative_update_11 | 2019:cumulative_update_2 | 2019:cumulative_update_3 | 2019:cumulative_update_4 | 2019:cumulative_update_5 | 2019:cumulative_update_6 | 2019:cumulative_update_7 | 2019:cumulative_update_8 | 2019:cumulative_update_9
  • microsoft exchange server 2016 cumulative update 23≥ 15.01.0, < 15.01.2507.032
  • microsoft exchange server 2019 cumulative update 12≥ 15.02.0, < 15.02.1118.037
  • microsoft exchange server 2019 cumulative update 13≥ 15.02.0, < 15.02.1258.025

1 vendor · 4 products

References

1 links